<pubdate>1988</pubdate>
</biblioentry>
+ <biblioentry id="sqltr-19075-6">
+ <title>SQL Technical Report</title>
+ <subtitle>Part 6: SQL support for JavaScript Object
+ Notation (JSON)</subtitle>
+ <edition>First Edition.</edition>
+ <biblioid>
+ <ulink url="http://standards.iso.org/ittf/PubliclyAvailableStandards/c067367_ISO_IEC_TR_19075-6_2017.zip"></ulink>.
+ </biblioid>
+ <pubdate>2017.</pubdate>
+ </biblioentry>
+
</bibliodiv>
<bibliodiv>
</sect1>
<sect1 id="functions-json">
- <title>JSON Functions and Operators</title>
+ <title>JSON Functions, Operators, and Expressions</title>
+
+ <para>
+ The functions, operators, and expressions described in this section
+ operate on JSON data:
+ </para>
+
+ <itemizedlist>
+ <listitem>
+ <para>
+ SQL/JSON path expressions
+ (see <xref linkend="functions-sqljson-path"/>).
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ PostgreSQL-specific functions and operators for JSON
+ data types (see <xref linkend="functions-pgjson"/>).
+ </para>
+ </listitem>
+ </itemizedlist>
+
+ <para>
+ To learn more about the SQL/JSON standard, see
+ <xref linkend="sqltr-19075-6"/>. For details on JSON types
+ supported in <productname>PostgreSQL</productname>,
+ see <xref linkend="datatype-json"/>.
+ </para>
+
+ <sect2 id="functions-sqljson-path">
+ <title>SQL/JSON Path Expressions</title>
+ <indexterm zone="functions-json">
+ <primary>SQL/JSON</primary>
+ <secondary>path expressions</secondary>
+ </indexterm>
+
+ <para>
+ SQL/JSON path expressions specify the items to be retrieved
+ from the JSON data, similar to XPath expressions used
+ for SQL access to XML. In <productname>PostgreSQL</productname>,
+ path expressions are implemented as the <type>jsonpath</type>
+ data type, described in <xref linkend="datatype-jsonpath"/>.
+ </para>
+
+ <para>JSON query functions and operators
+ pass the provided path expression to the <firstterm>path engine</firstterm>
+ for evaluation. If the expression matches the JSON data to be queried,
+ the corresponding SQL/JSON item is returned.
+ Path expressions are written in the SQL/JSON path language
+ and can also include arithmetic expressions and functions.
+ Query functions treat the provided expression as a
+ text string, so it must be enclosed in single quotes.
+ </para>
+
+ <para>
+ A path expression consists of a sequence of elements allowed
+ by the <type>jsonpath</type> data type.
+ The path expression is evaluated from left to right, but
+ you can use parentheses to change the order of operations.
+ If the evaluation is successful, a sequence of SQL/JSON items
+ (<firstterm>SQL/JSON sequence</firstterm>) is produced,
+ and the evaluation result is returned to the JSON query function
+ that completes the specified computation.
+ </para>
+
+ <para>
+ To refer to the JSON data to be queried (the
+ <firstterm>context item</firstterm>), use the <literal>$</literal> sign
+ in the path expression. It can be followed by one or more
+ <link linkend="type-jsonpath-accessors">accessor operators</link>,
+ which go down the JSON structure level by level to retrieve the
+ content of context item. Each operator that follows deals with the
+ result of the previous evaluation step.
+ </para>
+
+ <para>
+ For example, suppose you have some JSON data from a GPS tracker that you
+ would like to parse, such as:
+<programlisting>
+{ "track" :
+ {
+ "segments" : [
+ { "location": [ 47.763, 13.4034 ],
+ "start time": "2018-10-14 10:05:14",
+ "HR": 73
+ },
+ { "location": [ 47.706, 13.2635 ],
+ "start time": "2018-10-14 10:39:21",
+ "HR": 130
+ } ]
+ }
+}
+</programlisting>
+ </para>
+
+ <para>
+ To retrieve the available track segments, you need to use the
+ <literal>.<replaceable>key</replaceable></literal> accessor
+ operator for all the preceding JSON objects:
+<programlisting>
+'$.track.segments'
+</programlisting>
+ </para>
+
+ <para>
+ If the item to retrieve is an element of an array, you have
+ to unnest this array using the [*] operator. For example,
+ the following path will return location coordinates for all
+ the available track segments:
+<programlisting>
+'$.track.segments[*].location'
+</programlisting>
+ </para>
+
+ <para>
+ To return the coordinates of the first segment only, you can
+ specify the corresponding subscript in the <literal>[]</literal>
+ accessor operator. Note that the SQL/JSON arrays are 0-relative:
+<programlisting>
+'$.track.segments[0].location'
+</programlisting>
+ </para>
+
+ <para>
+ The result of each path evaluation step can be processed
+ by one or more <type>jsonpath</type> operators and methods
+ listed in <xref linkend="functions-sqljson-path-operators"/>.
+ Each method must be preceded by a dot, while arithmetic and boolean
+ operators are separated from the operands by spaces. For example,
+ you can get an array size:
+<programlisting>
+'$.track.segments.size()'
+</programlisting>
+ For more examples of using <type>jsonpath</type> operators
+ and methods within path expressions, see
+ <xref linkend="functions-sqljson-path-operators"/>.
+ </para>
+
+ <para>
+ When defining the path, you can also use one or more
+ <firstterm>filter expressions</firstterm>, which work similar to
+ the <literal>WHERE</literal> clause in SQL. Each filter expression
+ can provide one or more filtering conditions that are applied
+ to the result of the path evaluation. Each filter expression must
+ be enclosed in parentheses and preceded by a question mark.
+ Filter expressions are evaluated from left to right and can be nested.
+ The <literal>@</literal> variable denotes the current path evaluation
+ result to be filtered, and can be followed by one or more accessor
+ operators to define the JSON element by which to filter the result.
+ Functions and operators that can be used in the filtering condition
+ are listed in <xref linkend="functions-sqljson-filter-ex-table"/>.
+ SQL/JSON defines three-valued logic, so the result of the filter
+ expression may be <literal>true</literal>, <literal>false</literal>,
+ or <literal>unknown</literal>. The <literal>unknown</literal> value
+ plays the same role as SQL <literal>NULL</literal>. Further path
+ evaluation steps use only those items for which filter expressions
+ return true.
+ </para>
+
+ <para>
+ Suppose you would like to retrieve all heart rate values higher
+ than 130. You can achieve this using the following expression:
+<programlisting>
+'$.track.segments[*].HR ? (@ > 130)'
+</programlisting>
+ </para>
+
+ <para>
+ To get the start time of segments with such values instead, you have to
+ filter out irrelevant segments before returning the start time, so the
+ filter is applied to the previous step and the path in the filtering
+ condition is different:
+<programlisting>
+'$.track.segments[*] ? (@.HR > 130)."start time"'
+</programlisting>
+ </para>
+
+ <para>
+ You can use several filter expressions on the same nesting level, if
+ required. For example, the following expression selects all segments
+ that contain locations with relevant coordinates and high heart rate values:
+<programlisting>
+'$.track.segments[*] ? (@.location[1] < 13.4) ? (@.HR > 130)."start time"'
+</programlisting>
+ </para>
+
+ <para>
+ Using filter expressions at different nesting levels is also allowed.
+ The following example first filters all segments by location, and then
+ returns high heart rate values for these segments, if available:
+<programlisting>
+'$.track.segments[*] ? (@.location[1] < 13.4).HR ? (@ > 130)'
+</programlisting>
+ </para>
+
+ <para>
+ You can also nest filters within each other:
+<programlisting>
+'$.track ? (@.segments[*] ? (@.HR > 130)).segments.size()'
+</programlisting>
+ This expression returns the size of the track if it contains any
+ segments with high heart rate values, or an empty sequence otherwise.
+ </para>
+
+ <para>
+ <productname>PostgreSQL</productname>'s implementation of SQL/JSON path
+ language has the following deviations from the SQL/JSON standard:
+ </para>
+
+ <itemizedlist>
+ <listitem>
+ <para>
+ <literal>.datetime()</literal> item method is not implemented yet
+ mainly because immutable <type>jsonpath</type> functions and operators
+ cannot reference session timezone, which is used in some datetime
+ operations. Datetime support will be added to <type>jsonpath</type>
+ in future versions of <productname>PostgreSQL</productname>.
+ </para>
+ </listitem>
+
+ <listitem>
+ <para>
+ A path expression can be a boolean predicate, although the SQL/JSON
+ standard allows predicates only in filters. This is necessary for
+ implementation of the <literal>@@</literal> operator. For example,
+ the following<type>jsonpath</type> expression is valid in
+ <productname>PostgreSQL</productname>:
+<programlisting>
+'$.track.segments[*].HR < 70'
+</programlisting>
+ </para>
+ </listitem>
+ </itemizedlist>
+
+ <sect3 id="strict-and-lax-modes">
+ <title>Strict and Lax Modes</title>
+ <para>
+ When you query JSON data, the path expression may not match the
+ actual JSON data structure. An attempt to access a non-existent
+ member of an object or element of an array results in a
+ structural error. SQL/JSON path expressions have two modes
+ of handling structural errors:
+ </para>
+
+ <itemizedlist>
+ <listitem>
+ <para>
+ lax (default) — the path engine implicitly adapts
+ the queried data to the specified path.
+ Any remaining structural errors are suppressed and converted
+ to empty SQL/JSON sequences.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ strict — if a structural error occurs, an error is raised.
+ </para>
+ </listitem>
+ </itemizedlist>
+
+ <para>
+ The lax mode facilitates matching of a JSON document structure and path
+ expression if the JSON data does not conform to the expected schema.
+ If an operand does not match the requirements of a particular operation,
+ it can be automatically wrapped as an SQL/JSON array or unwrapped by
+ converting its elements into an SQL/JSON sequence before performing
+ this operation. Besides, comparison operators automatically unwrap their
+ operands in the lax mode, so you can compare SQL/JSON arrays
+ out-of-the-box. Arrays of size 1 are interchangeable with a singleton.
+ Automatic unwrapping is not performed only when:
+ <itemizedlist>
+ <listitem>
+ <para>
+ The path expression contains <literal>type()</literal> or
+ <literal>size()</literal> methods that return the type
+ and the number of elements in the array, respectively.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ The queried JSON data contain nested arrays. In this case, only
+ the outermost array is unwrapped, while all the inner arrays
+ remain unchanged. Thus, implicit unwrapping can only go one
+ level down within each path evaluation step.
+ </para>
+ </listitem>
+ </itemizedlist>
+ </para>
+
+ <para>
+ For example, when querying the GPS data listed above, you can
+ abstract from the fact that it stores an array of segments
+ when using the lax mode:
+<programlisting>
+'lax $.track.segments.location'
+</programlisting>
+ </para>
+
+ <para>
+ In the strict mode, the specified path must exactly match the structure of
+ the queried JSON document to return an SQL/JSON item, so using this
+ path expression will cause an error. To get the same result as in
+ the lax mode, you have to explicitly unwrap the
+ <literal>segments</literal> array:
+<programlisting>
+'strict $.track.segments[*].location'
+</programlisting>
+ </para>
+
+ </sect3>
+
+ <sect3 id="functions-sqljson-path-operators">
+ <title>SQL/JSON Path Operators and Methods</title>
+
+ <table id="functions-sqljson-op-table">
+ <title><type>jsonpath</type> Operators and Methods</title>
+ <tgroup cols="5">
+ <thead>
+ <row>
+ <entry>Operator/Method</entry>
+ <entry>Description</entry>
+ <entry>Example JSON</entry>
+ <entry>Example Query</entry>
+ <entry>Result</entry>
+ </row>
+ </thead>
+ <tbody>
+ <row>
+ <entry><literal>+</literal> (unary)</entry>
+ <entry>Plus operator that iterates over the SQL/JSON sequence</entry>
+ <entry><literal>{"x": [2.85, -14.7, -9.4]}</literal></entry>
+ <entry><literal>+ $.x.floor()</literal></entry>
+ <entry><literal>2, -15, -10</literal></entry>
+ </row>
+ <row>
+ <entry><literal>-</literal> (unary)</entry>
+ <entry>Minus operator that iterates over the SQL/JSON sequence</entry>
+ <entry><literal>{"x": [2.85, -14.7, -9.4]}</literal></entry>
+ <entry><literal>- $.x.floor()</literal></entry>
+ <entry><literal>-2, 15, 10</literal></entry>
+ </row>
+ <row>
+ <entry><literal>+</literal> (binary)</entry>
+ <entry>Addition</entry>
+ <entry><literal>[2]</literal></entry>
+ <entry><literal>2 + $[0]</literal></entry>
+ <entry><literal>4</literal></entry>
+ </row>
+ <row>
+ <entry><literal>-</literal> (binary)</entry>
+ <entry>Subtraction</entry>
+ <entry><literal>[2]</literal></entry>
+ <entry><literal>4 - $[0]</literal></entry>
+ <entry><literal>2</literal></entry>
+ </row>
+ <row>
+ <entry><literal>*</literal></entry>
+ <entry>Multiplication</entry>
+ <entry><literal>[4]</literal></entry>
+ <entry><literal>2 * $[0]</literal></entry>
+ <entry><literal>8</literal></entry>
+ </row>
+ <row>
+ <entry><literal>/</literal></entry>
+ <entry>Division</entry>
+ <entry><literal>[8]</literal></entry>
+ <entry><literal>$[0] / 2</literal></entry>
+ <entry><literal>4</literal></entry>
+ </row>
+ <row>
+ <entry><literal>%</literal></entry>
+ <entry>Modulus</entry>
+ <entry><literal>[32]</literal></entry>
+ <entry><literal>$[0] % 10</literal></entry>
+ <entry><literal>2</literal></entry>
+ </row>
+ <row>
+ <entry><literal>type()</literal></entry>
+ <entry>Type of the SQL/JSON item</entry>
+ <entry><literal>[1, "2", {}]</literal></entry>
+ <entry><literal>$[*].type()</literal></entry>
+ <entry><literal>"number", "string", "object"</literal></entry>
+ </row>
+ <row>
+ <entry><literal>size()</literal></entry>
+ <entry>Size of the SQL/JSON item</entry>
+ <entry><literal>{"m": [11, 15]}</literal></entry>
+ <entry><literal>$.m.size()</literal></entry>
+ <entry><literal>2</literal></entry>
+ </row>
+ <row>
+ <entry><literal>double()</literal></entry>
+ <entry>Approximate numeric value converted from a string</entry>
+ <entry><literal>{"len": "1.9"}</literal></entry>
+ <entry><literal>$.len.double() * 2</literal></entry>
+ <entry><literal>3.8</literal></entry>
+ </row>
+ <row>
+ <entry><literal>ceiling()</literal></entry>
+ <entry>Nearest integer greater than or equal to the SQL/JSON number</entry>
+ <entry><literal>{"h": 1.3}</literal></entry>
+ <entry><literal>$.h.ceiling()</literal></entry>
+ <entry><literal>2</literal></entry>
+ </row>
+ <row>
+ <entry><literal>floor()</literal></entry>
+ <entry>Nearest integer less than or equal to the SQL/JSON number</entry>
+ <entry><literal>{"h": 1.3}</literal></entry>
+ <entry><literal>$.h.floor()</literal></entry>
+ <entry><literal>1</literal></entry>
+ </row>
+ <row>
+ <entry><literal>abs()</literal></entry>
+ <entry>Absolute value of the SQL/JSON number</entry>
+ <entry><literal>{"z": -0.3}</literal></entry>
+ <entry><literal>$.z.abs()</literal></entry>
+ <entry><literal>0.3</literal></entry>
+ </row>
+ <row>
+ <entry><literal>keyvalue()</literal></entry>
+ <entry>
+ Sequence of object's key-value pairs represented as array of objects
+ containing three fields (<literal>"key"</literal>,
+ <literal>"value"</literal>, and <literal>"id"</literal>).
+ <literal>"id"</literal> is an unique identifier of the object
+ key-value pair belongs to.
+ </entry>
+ <entry><literal>{"x": "20", "y": 32}</literal></entry>
+ <entry><literal>$.keyvalue()</literal></entry>
+ <entry><literal>{"key": "x", "value": "20", "id": 0}, {"key": "y", "value": 32, "id": 0}</literal></entry>
+ </row>
+ </tbody>
+ </tgroup>
+ </table>
+
+ <table id="functions-sqljson-filter-ex-table">
+ <title><type>jsonpath</type> Filter Expression Elements</title>
+ <tgroup cols="5">
+ <thead>
+ <row>
+ <entry>Value/Predicate</entry>
+ <entry>Description</entry>
+ <entry>Example JSON</entry>
+ <entry>Example Query</entry>
+ <entry>Result</entry>
+ </row>
+ </thead>
+ <tbody>
+ <row>
+ <entry><literal>==</literal></entry>
+ <entry>Equality operator</entry>
+ <entry><literal>[1, 2, 1, 3]</literal></entry>
+ <entry><literal>$[*] ? (@ == 1)</literal></entry>
+ <entry><literal>1, 1</literal></entry>
+ </row>
+ <row>
+ <entry><literal>!=</literal></entry>
+ <entry>Non-equality operator</entry>
+ <entry><literal>[1, 2, 1, 3]</literal></entry>
+ <entry><literal>$[*] ? (@ != 1)</literal></entry>
+ <entry><literal>2, 3</literal></entry>
+ </row>
+ <row>
+ <entry><literal><></literal></entry>
+ <entry>Non-equality operator (same as <literal>!=</literal>)</entry>
+ <entry><literal>[1, 2, 1, 3]</literal></entry>
+ <entry><literal>$[*] ? (@ <> 1)</literal></entry>
+ <entry><literal>2, 3</literal></entry>
+ </row>
+ <row>
+ <entry><literal><</literal></entry>
+ <entry>Less-than operator</entry>
+ <entry><literal>[1, 2, 3]</literal></entry>
+ <entry><literal>$[*] ? (@ < 2)</literal></entry>
+ <entry><literal>1, 2</literal></entry>
+ </row>
+ <row>
+ <entry><literal><=</literal></entry>
+ <entry>Less-than-or-equal-to operator</entry>
+ <entry><literal>[1, 2, 3]</literal></entry>
+ <entry><literal>$[*] ? (@ < 2)</literal></entry>
+ <entry><literal>1</literal></entry>
+ </row>
+ <row>
+ <entry><literal>></literal></entry>
+ <entry>Greater-than operator</entry>
+ <entry><literal>[1, 2, 3]</literal></entry>
+ <entry><literal>$[*] ? (@ > 2)</literal></entry>
+ <entry><literal>3</literal></entry>
+ </row>
+ <row>
+ <entry><literal>></literal></entry>
+ <entry>Greater-than-or-equal-to operator</entry>
+ <entry><literal>[1, 2, 3]</literal></entry>
+ <entry><literal>$[*] ? (@ >= 2)</literal></entry>
+ <entry><literal>2, 3</literal></entry>
+ </row>
+ <row>
+ <entry><literal>true</literal></entry>
+ <entry>Value used to perform comparison with JSON <literal>true</literal> literal</entry>
+ <entry><literal>[{"name": "John", "parent": false},
+ {"name": "Chris", "parent": true}]</literal></entry>
+ <entry><literal>$[*] ? (@.parent == true)</literal></entry>
+ <entry><literal>{"name": "Chris", "parent": true}</literal></entry>
+ </row>
+ <row>
+ <entry><literal>false</literal></entry>
+ <entry>Value used to perform comparison with JSON <literal>false</literal> literal</entry>
+ <entry><literal>[{"name": "John", "parent": false},
+ {"name": "Chris", "parent": true}]</literal></entry>
+ <entry><literal>$[*] ? (@.parent == false)</literal></entry>
+ <entry><literal>{"name": "John", "parent": false}</literal></entry>
+ </row>
+ <row>
+ <entry><literal>null</literal></entry>
+ <entry>Value used to perform comparison with JSON <literal>null</literal> value</entry>
+ <entry><literal>[{"name": "Mary", "job": null},
+ {"name": "Michael", "job": "driver"}]</literal></entry>
+ <entry><literal>$[*] ? (@.job == null) .name</literal></entry>
+ <entry><literal>"Mary"</literal></entry>
+ </row>
+ <row>
+ <entry><literal>&&</literal></entry>
+ <entry>Boolean AND</entry>
+ <entry><literal>[1, 3, 7]</literal></entry>
+ <entry><literal>$[*] ? (@ > 1 && @ < 5)</literal></entry>
+ <entry><literal>3</literal></entry>
+ </row>
+ <row>
+ <entry><literal>||</literal></entry>
+ <entry>Boolean OR</entry>
+ <entry><literal>[1, 3, 7]</literal></entry>
+ <entry><literal>$[*] ? (@ < 1 || @ > 5)</literal></entry>
+ <entry><literal>7</literal></entry>
+ </row>
+ <row>
+ <entry><literal>!</literal></entry>
+ <entry>Boolean NOT</entry>
+ <entry><literal>[1, 3, 7]</literal></entry>
+ <entry><literal>$[*] ? (!(@ < 5))</literal></entry>
+ <entry><literal>7</literal></entry>
+ </row>
+ <row>
+ <entry><literal>like_regex</literal></entry>
+ <entry>Tests pattern matching with POSIX regular expressions</entry>
+ <entry><literal>["abc", "abd", "aBdC", "abdacb", "babc"]</literal></entry>
+ <entry><literal>$[*] ? (@ like_regex "^ab.*c" flag "i")</literal></entry>
+ <entry><literal>"abc", "aBdC", "abdacb"</literal></entry>
+ </row>
+ <row>
+ <entry><literal>starts with</literal></entry>
+ <entry>Tests whether the second operand is an initial substring of the first operand</entry>
+ <entry><literal>["John Smith", "Mary Stone", "Bob Johnson"]</literal></entry>
+ <entry><literal>$[*] ? (@ starts with "John")</literal></entry>
+ <entry><literal>"John Smith"</literal></entry>
+ </row>
+ <row>
+ <entry><literal>exists</literal></entry>
+ <entry>Tests whether a path expression has at least one SQL/JSON item</entry>
+ <entry><literal>{"x": [1, 2], "y": [2, 4]}</literal></entry>
+ <entry><literal>strict $.* ? (exists (@ ? (@[*] > 2)))</literal></entry>
+ <entry><literal>2, 4</literal></entry>
+ </row>
+ <row>
+ <entry><literal>is unknown</literal></entry>
+ <entry>Tests whether a boolean condition is <literal>unknown</literal></entry>
+ <entry><literal>[-1, 2, 7, "infinity"]</literal></entry>
+ <entry><literal>$[*] ? ((@ > 0) is unknown)</literal></entry>
+ <entry><literal>"infinity"</literal></entry>
+ </row>
+ </tbody>
+ </tgroup>
+ </table>
+ </sect3>
+
+ </sect2>
+ <sect2 id="functions-pgjson">
+ <title>JSON Functions and Operators</title>
<indexterm zone="functions-json">
<primary>JSON</primary>
<secondary>functions and operators</secondary>
</indexterm>
+ <para>
<xref linkend="functions-json-op-table"/> shows the operators that
- are available for use with the two JSON data types (see <xref
+ are available for use with JSON data types (see <xref
linkend="datatype-json"/>).
</para>
<table id="functions-json-op-table">
<title><type>json</type> and <type>jsonb</type> Operators</title>
- <tgroup cols="5">
+ <tgroup cols="6">
<thead>
<row>
<entry>Operator</entry>
<entry>Right Operand Type</entry>
+ <entry>Return type</entry>
<entry>Description</entry>
<entry>Example</entry>
<entry>Example Result</entry>
<row>
<entry><literal>-></literal></entry>
<entry><type>int</type></entry>
+ <entry><type>json</type> or <type>jsonb</type></entry>
<entry>Get JSON array element (indexed from zero, negative
integers count from the end)</entry>
<entry><literal>'[{"a":"foo"},{"b":"bar"},{"c":"baz"}]'::json->2</literal></entry>
<row>
<entry><literal>-></literal></entry>
<entry><type>text</type></entry>
+ <entry><type>json</type> or <type>jsonb</type></entry>
<entry>Get JSON object field by key</entry>
<entry><literal>'{"a": {"b":"foo"}}'::json->'a'</literal></entry>
<entry><literal>{"b":"foo"}</literal></entry>
<row>
<entry><literal>->></literal></entry>
<entry><type>int</type></entry>
+ <entry><type>text</type></entry>
<entry>Get JSON array element as <type>text</type></entry>
<entry><literal>'[1,2,3]'::json->>2</literal></entry>
<entry><literal>3</literal></entry>
<row>
<entry><literal>->></literal></entry>
<entry><type>text</type></entry>
+ <entry><type>text</type></entry>
<entry>Get JSON object field as <type>text</type></entry>
<entry><literal>'{"a":1,"b":2}'::json->>'b'</literal></entry>
<entry><literal>2</literal></entry>
<row>
<entry><literal>#></literal></entry>
<entry><type>text[]</type></entry>
- <entry>Get JSON object at specified path</entry>
+ <entry><type>json</type> or <type>jsonb</type></entry>
+ <entry>Get JSON object at the specified path</entry>
<entry><literal>'{"a": {"b":{"c": "foo"}}}'::json#>'{a,b}'</literal></entry>
<entry><literal>{"c": "foo"}</literal></entry>
</row>
<row>
<entry><literal>#>></literal></entry>
<entry><type>text[]</type></entry>
- <entry>Get JSON object at specified path as <type>text</type></entry>
+ <entry><type>text</type></entry>
+ <entry>Get JSON object at the specified path as <type>text</type></entry>
<entry><literal>'{"a":[1,2,3],"b":[4,5,6]}'::json#>>'{a,2}'</literal></entry>
<entry><literal>3</literal></entry>
</row>
JSON arrays, negative integers count from the end)</entry>
<entry><literal>'["a", {"b":1}]'::jsonb #- '{1,b}'</literal></entry>
</row>
+ <row>
+ <entry><literal>@?</literal></entry>
+ <entry><type>jsonpath</type></entry>
+ <entry>Does JSON path returns any item for the specified JSON value?</entry>
+ <entry><literal>'{"a":[1,2,3,4,5]}'::jsonb @? '$.a[*] ? (@ > 2)'</literal></entry>
+ </row>
+ <row>
+ <entry><literal>@@</literal></entry>
+ <entry><type>jsonpath</type></entry>
+ <entry>JSON path predicate check result for the specified JSON value.
+ Only first result item is taken into account. If there is no results
+ or first result item is not bool, then <literal>NULL</literal>
+ is returned.</entry>
+ <entry><literal>'{"a":[1,2,3,4,5]}'::jsonb @@ '$.a[*] > 2'</literal></entry>
+ </row>
</tbody>
</tgroup>
</table>
</para>
</note>
+ <note>
+ <para>
+ The <literal>@?</literal> and <literal>@@</literal> operators suppress
+ errors including: lacking object field or array element, unexpected JSON
+ item type.
+ This behavior might be helpful while searching over JSON document
+ collections of varying structure.
+ </para>
+ </note>
+
<para>
<xref linkend="functions-json-creation-table"/> shows the functions that are
available for creating <type>json</type> and <type>jsonb</type> values.
<indexterm>
<primary>jsonb_pretty</primary>
</indexterm>
+ <indexterm>
+ <primary>jsonb_path_exists</primary>
+ </indexterm>
+ <indexterm>
+ <primary>jsonb_path_match</primary>
+ </indexterm>
+ <indexterm>
+ <primary>jsonb_path_query</primary>
+ </indexterm>
+ <indexterm>
+ <primary>jsonb_path_query_array</primary>
+ </indexterm>
+ <indexterm>
+ <primary>jsonb_path_query_first</primary>
+ </indexterm>
<table id="functions-json-processing-table">
<title>JSON Processing Functions</title>
</programlisting>
</entry>
</row>
+ <row>
+ <entry>
+ <para><literal>
+ jsonb_path_exists(target jsonb, path jsonpath [, vars jsonb, silent bool])
+ </literal></para>
+ </entry>
+ <entry><type>boolean</type></entry>
+ <entry>
+ Checks whether JSON path returns any item for the specified JSON
+ value.
+ </entry>
+ <entry>
+ <para><literal>
+ jsonb_path_exists('{"a":[1,2,3,4,5]}', '$.a[*] ? (@ >= $min && @ <= $max)', '{"min":2,"max":4}')
+ </literal></para>
+ </entry>
+ <entry>
+ <para><literal>true</literal></para>
+ </entry>
+ </row>
+ <row>
+ <entry>
+ <para><literal>
+ jsonb_path_match(target jsonb, path jsonpath [, vars jsonb, silent bool])
+ </literal></para>
+ </entry>
+ <entry><type>boolean</type></entry>
+ <entry>
+ Returns JSON path predicate result for the specified JSON value.
+ Only first result item is taken into account. If there is no results
+ or first result item is not bool, then <literal>NULL</literal>
+ is returned.
+ </entry>
+ <entry>
+ <para><literal>
+ jsonb_path_match('{"a":[1,2,3,4,5]}', 'exists($.a[*] ? (@ >= $min && @ <= $max))', '{"min":2,"max":4}')
+ </literal></para>
+ </entry>
+ <entry>
+ <para><literal>true</literal></para>
+ </entry>
+ </row>
+ <row>
+ <entry>
+ <para><literal>
+ jsonb_path_query(target jsonb, path jsonpath [, vars jsonb, silent bool])
+ </literal></para>
+ </entry>
+ <entry><type>setof jsonb</type></entry>
+ <entry>
+ Gets all JSON items returned by JSON path for the specified JSON
+ value.
+ </entry>
+ <entry>
+ <para><literal>
+ select * jsonb_path_query('{"a":[1,2,3,4,5]}', '$.a[*] ? (@ >= $min && @ <= $max)', '{"min":2,"max":4}');
+ </literal></para>
+ </entry>
+ <entry>
+ <para>
+ <programlisting>
+ jsonb_path_query
+------------------
+ 2
+ 3
+ 4
+ </programlisting>
+ </para>
+ </entry>
+ </row>
+ <row>
+ <entry>
+ <para><literal>
+ jsonb_path_query_array(target jsonb, path jsonpath [, vars jsonb, silent bool])
+ </literal></para>
+ </entry>
+ <entry><type>jsonb</type></entry>
+ <entry>
+ Gets all JSON items returned by JSON path for the specified JSON
+ value and wraps result into an array.
+ </entry>
+ <entry>
+ <para><literal>
+ jsonb_path_query_array('{"a":[1,2,3,4,5]}', '$.a[*] ? (@ >= $min && @ <= $max)', '{"min":2,"max":4}')
+ </literal></para>
+ </entry>
+ <entry>
+ <para><literal>[2, 3, 4]</literal></para>
+ </entry>
+ </row>
+ <row>
+ <entry>
+ <para><literal>
+ jsonb_path_query_first(target jsonb, path jsonpath [, vars jsonb, silent bool])
+ </literal></para>
+ </entry>
+ <entry><type>jsonb</type></entry>
+ <entry>
+ Gets the first JSON item returned by JSON path for the specified JSON
+ value. Returns <literal>NULL</literal> on no results.
+ </entry>
+ <entry>
+ <para><literal>
+ jsonb_path_query_first('{"a":[1,2,3,4,5]}', '$.a[*] ? (@ >= $min && @ <= $max)', '{"min":2,"max":4}')
+ </literal></para>
+ </entry>
+ <entry>
+ <para><literal>2</literal></para>
+ </entry>
+ </row>
</tbody>
</tgroup>
</table>
JSON fields that do not appear in the target row type will be
omitted from the output, and target columns that do not match any
JSON field will simply be NULL.
+
</para>
</note>
</para>
</note>
+ <note>
+ <para>
+ The <literal>jsonb_path_exists</literal>, <literal>jsonb_path_match</literal>,
+ <literal>jsonb_path_query</literal>, <literal>jsonb_path_query_array</literal> and
+ <literal>jsonb_path_query_first</literal>
+ functions have optional <literal>vars</literal> and <literal>silent</literal>
+ argument.
+ </para>
+ <para>
+ When <literal>vars</literal> argument is specified, it constitutes an object
+ contained variables to be substituted into <literal>jsonpath</literal>
+ expression.
+ </para>
+ <para>
+ When <literal>silent</literal> argument is specified and has
+ <literal>true</literal> value, the same errors are suppressed as it is in
+ the <literal>@?</literal> and <literal>@@</literal> operators.
+ </para>
+ </note>
+
<para>
See also <xref linkend="functions-aggregate"/> for the aggregate
function <function>json_agg</function> which aggregates record
<function>jsonb_agg</function> and <function>jsonb_object_agg</function>.
</para>
+ </sect2>
</sect1>
<sect1 id="functions-sequence">
</para>
<para>
- There are two JSON data types: <type>json</type> and <type>jsonb</type>.
- They accept <emphasis>almost</emphasis> identical sets of values as
+ <productname>PostgreSQL</productname> offers two types for storing JSON
+ data: <type>json</type> and <type>jsonb</type>. To implement effective query
+ mechanisms for these data types, <productname>PostgreSQL</productname>
+ also provides the <type>jsonpath</type> data type described in
+ <xref linkend="datatype-jsonpath"/>.
+ </para>
+
+ <para>
+ The <type>json</type> and <type>jsonb</type> data types
+ accept <emphasis>almost</emphasis> identical sets of values as
input. The major practical difference is one of efficiency. The
<type>json</type> data type stores an exact copy of the input text,
which processing functions must reparse on each execution; while
in this example, even though those are semantically insignificant for
purposes such as equality checks.
</para>
+
+ <para>
+ For the list of built-in functions and operators available for
+ constructing and processing JSON values, see <xref linkend="functions-json"/>.
+ </para>
</sect2>
<sect2 id="json-doc-design">
lists, and scalars, as appropriate.
</para>
</sect2>
+
+ <sect2 id="datatype-jsonpath">
+ <title>jsonpath Type</title>
+
+ <indexterm zone="datatype-jsonpath">
+ <primary>jsonpath</primary>
+ </indexterm>
+
+ <para>
+ The <type>jsonpath</type> type implements support for the SQL/JSON path language
+ in <productname>PostgreSQL</productname> to effectively query JSON data.
+ It provides a binary representation of the parsed SQL/JSON path
+ expression that specifies the items to be retrieved by the path
+ engine from the JSON data for further processing with the
+ SQL/JSON query functions.
+ </para>
+
+ <para>
+ The SQL/JSON path language is fully integrated into the SQL engine:
+ the semantics of its predicates and operators generally follow SQL.
+ At the same time, to provide a most natural way of working with JSON data,
+ SQL/JSON path syntax uses some of the JavaScript conventions:
+ </para>
+
+ <itemizedlist>
+ <listitem>
+ <para>
+ Dot <literal>.</literal> is used for member access.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Square brackets <literal>[]</literal> are used for array access.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ SQL/JSON arrays are 0-relative, unlike regular SQL arrays that start from 1.
+ </para>
+ </listitem>
+ </itemizedlist>
+
+ <para>
+ An SQL/JSON path expression is an SQL character string literal,
+ so it must be enclosed in single quotes when passed to an SQL/JSON
+ query function. Following the JavaScript
+ conventions, character string literals within the path expression
+ must be enclosed in double quotes. Any single quotes within this
+ character string literal must be escaped with a single quote
+ by the SQL convention.
+ </para>
+
+ <para>
+ A path expression consists of a sequence of path elements,
+ which can be the following:
+ <itemizedlist>
+ <listitem>
+ <para>
+ Path literals of JSON primitive types:
+ Unicode text, numeric, true, false, or null.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Path variables listed in <xref linkend="type-jsonpath-variables"/>.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Accessor operators listed in <xref linkend="type-jsonpath-accessors"/>.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ <type>jsonpath</type> operators and methods listed
+ in <xref linkend="functions-sqljson-path-operators"/>
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Parentheses, which can be used to provide filter expressions
+ or define the order of path evaluation.
+ </para>
+ </listitem>
+ </itemizedlist>
+ </para>
+
+ <para>
+ For details on using <type>jsonpath</type> expressions with SQL/JSON
+ query functions, see <xref linkend="functions-sqljson-path"/>.
+ </para>
+
+ <table id="type-jsonpath-variables">
+ <title><type>jsonpath</type> Variables</title>
+ <tgroup cols="2">
+ <thead>
+ <row>
+ <entry>Variable</entry>
+ <entry>Description</entry>
+ </row>
+ </thead>
+ <tbody>
+ <row>
+ <entry><literal>$</literal></entry>
+ <entry>A variable representing the JSON text to be queried
+ (the <firstterm>context item</firstterm>).
+ </entry>
+ </row>
+ <row>
+ <entry><literal>$varname</literal></entry>
+ <entry>A named variable. Its value must be set in the
+ <command>PASSING</command> clause of an SQL/JSON query function.
+ <!-- TBD: See <xref linkend="sqljson-input-clause"/> -->
+ for details.
+ </entry>
+ </row>
+ <row>
+ <entry><literal>@</literal></entry>
+ <entry>A variable representing the result of path evaluation
+ in filter expressions.
+ </entry>
+ </row>
+ </tbody>
+ </tgroup>
+ </table>
+
+ <table id="type-jsonpath-accessors">
+ <title><type>jsonpath</type> Accessors</title>
+ <tgroup cols="2">
+ <thead>
+ <row>
+ <entry>Accessor Operator</entry>
+ <entry>Description</entry>
+ </row>
+ </thead>
+ <tbody>
+ <row>
+ <entry>
+ <para>
+ <literal>.<replaceable>key</replaceable></literal>
+ </para>
+ <para>
+ <literal>."$<replaceable>varname</replaceable>"</literal>
+ </para>
+ </entry>
+ <entry>
+ <para>
+ Member accessor that returns an object member with
+ the specified key. If the key name is a named variable
+ starting with <literal>$</literal> or does not meet the
+ JavaScript rules of an identifier, it must be enclosed in
+ double quotes as a character string literal.
+ </para>
+ </entry>
+ </row>
+ <row>
+ <entry>
+ <para>
+ <literal>.*</literal>
+ </para>
+ </entry>
+ <entry>
+ <para>
+ Wildcard member accessor that returns the values of all
+ members located at the top level of the current object.
+ </para>
+ </entry>
+ </row>
+ <row>
+ <entry>
+ <para>
+ <literal>.**</literal>
+ </para>
+ </entry>
+ <entry>
+ <para>
+ Recursive wildcard member accessor that processes all levels
+ of the JSON hierarchy of the current object and returns all
+ the member values, regardless of their nesting level. This
+ is a <productname>PostgreSQL</productname> extension of
+ the SQL/JSON standard.
+ </para>
+ </entry>
+ </row>
+ <row>
+ <entry>
+ <para>
+ <literal>[<replaceable>subscript</replaceable>, ...]</literal>
+ </para>
+ <para>
+ <literal>[<replaceable>subscript</replaceable> to last]</literal>
+ </para>
+ </entry>
+ <entry>
+ <para>
+ Array element accessor. The provided numeric subscripts return the
+ corresponding array elements. The first element in an array is
+ accessed with [0]. The <literal>last</literal> keyword denotes
+ the last subscript in an array and can be used to handle arrays
+ of unknown length.
+ </para>
+ </entry>
+ </row>
+ <row>
+ <entry>
+ <para>
+ <literal>[*]</literal>
+ </para>
+ </entry>
+ <entry>
+ <para>
+ Wildcard array element accessor that returns all array elements.
+ </para>
+ </entry>
+ </row>
+ </tbody>
+ </tgroup>
+ </table>
+
+ </sect2>
</sect1>
storage/lmgr/lwlocknames.h: storage/lmgr/generate-lwlocknames.pl storage/lmgr/lwlocknames.txt
$(MAKE) -C storage/lmgr lwlocknames.h lwlocknames.c
+utils/adt/jsonpath_gram.h: utils/adt/jsonpath_gram.y
+ $(MAKE) -C utils/adt jsonpath_gram.h
+
# run this unconditionally to avoid needing to know its dependencies here:
submake-catalog-headers:
$(MAKE) -C catalog distprep generated-header-symlinks
.PHONY: generated-headers
-generated-headers: $(top_builddir)/src/include/parser/gram.h $(top_builddir)/src/include/storage/lwlocknames.h submake-catalog-headers submake-utils-headers
+generated-headers: $(top_builddir)/src/include/parser/gram.h $(top_builddir)/src/include/storage/lwlocknames.h $(top_builddir)/src/include/utils/jsonpath_gram.h submake-catalog-headers submake-utils-headers
$(top_builddir)/src/include/parser/gram.h: parser/gram.h
prereqdir=`cd '$(dir $<)' >/dev/null && pwd` && \
cd '$(dir $@)' && rm -f $(notdir $@) && \
$(LN_S) "$$prereqdir/$(notdir $<)" .
+$(top_builddir)/src/include/utils/jsonpath_gram.h: utils/adt/jsonpath_gram.h
+ prereqdir=`cd '$(dir $<)' >/dev/null && pwd` && \
+ cd '$(dir $@)' && rm -f $(notdir $@) && \
+ $(LN_S) "$$prereqdir/$(notdir $<)" .
utils/probes.o: utils/probes.d $(SUBDIROBJS)
$(DTRACE) $(DTRACEFLAGS) -C -G -s $(call expand_subsys,$^) -o $@
$(MAKE) -C replication repl_gram.c repl_scanner.c syncrep_gram.c syncrep_scanner.c
$(MAKE) -C storage/lmgr lwlocknames.h lwlocknames.c
$(MAKE) -C utils distprep
+ $(MAKE) -C utils/adt jsonpath_gram.c jsonpath_gram.h jsonpath_scan.c
$(MAKE) -C utils/misc guc-file.c
$(MAKE) -C utils/sort qsort_tuple.c
storage/lmgr/lwlocknames.c \
storage/lmgr/lwlocknames.h \
utils/misc/guc-file.c \
+ utils/adt/jsonpath_gram.h \
utils/sort/qsort_tuple.c
STRICT IMMUTABLE PARALLEL SAFE
AS 'jsonb_insert';
+CREATE OR REPLACE FUNCTION
+ jsonb_path_exists(target jsonb, path jsonpath, vars jsonb DEFAULT '{}',
+ silent boolean DEFAULT false)
+RETURNS boolean
+LANGUAGE INTERNAL
+STRICT IMMUTABLE PARALLEL SAFE
+AS 'jsonb_path_exists';
+
+CREATE OR REPLACE FUNCTION
+ jsonb_path_match(target jsonb, path jsonpath, vars jsonb DEFAULT '{}',
+ silent boolean DEFAULT false)
+RETURNS boolean
+LANGUAGE INTERNAL
+STRICT IMMUTABLE PARALLEL SAFE
+AS 'jsonb_path_match';
+
+CREATE OR REPLACE FUNCTION
+ jsonb_path_query(target jsonb, path jsonpath, vars jsonb DEFAULT '{}',
+ silent boolean DEFAULT false)
+RETURNS SETOF jsonb
+LANGUAGE INTERNAL
+STRICT IMMUTABLE PARALLEL SAFE
+AS 'jsonb_path_query';
+
+CREATE OR REPLACE FUNCTION
+ jsonb_path_query_array(target jsonb, path jsonpath, vars jsonb DEFAULT '{}',
+ silent boolean DEFAULT false)
+RETURNS jsonb
+LANGUAGE INTERNAL
+STRICT IMMUTABLE PARALLEL SAFE
+AS 'jsonb_path_query_array';
+
+CREATE OR REPLACE FUNCTION
+ jsonb_path_query_first(target jsonb, path jsonpath, vars jsonb DEFAULT '{}',
+ silent boolean DEFAULT false)
+RETURNS jsonb
+LANGUAGE INTERNAL
+STRICT IMMUTABLE PARALLEL SAFE
+AS 'jsonb_path_query_first';
+
--
-- The default permissions for functions mean that anyone can execute them.
-- A number of functions shouldn't be executable by just anyone, but rather
--- /dev/null
+/jsonpath_gram.h
+/jsonpath_gram.c
+/jsonpath_scan.c
float.o format_type.o formatting.o genfile.o \
geo_ops.o geo_selfuncs.o geo_spgist.o inet_cidr_ntop.o inet_net_pton.o \
int.o int8.o json.o jsonb.o jsonb_gin.o jsonb_op.o jsonb_util.o \
- jsonfuncs.o like.o like_support.o lockfuncs.o \
- mac.o mac8.o misc.o name.o \
+ jsonfuncs.o jsonpath_gram.o jsonpath_scan.o jsonpath.o jsonpath_exec.o \
+ like.o like_support.o lockfuncs.o mac.o mac8.o misc.o name.o \
network.o network_gist.o network_selfuncs.o network_spgist.o \
numeric.o numutils.o oid.o oracle_compat.o \
orderedsetaggs.o partitionfuncs.o pg_locale.o pg_lsn.o \
txid.o uuid.o varbit.o varchar.o varlena.o version.o \
windowfuncs.o xid.o xml.o
+jsonpath_gram.c: BISONFLAGS += -d
+
+jsonpath_scan.c: FLEXFLAGS = -CF -p -p
+
+jsonpath_gram.h: jsonpath_gram.c ;
+
+# Force these dependencies to be known even without dependency info built:
+jsonpath_gram.o jsonpath_scan.o jsonpath_parser.o: jsonpath_gram.h
+
+# jsonpath_gram.c, jsonpath_gram.h, and jsonpath_scan.c are in the
+# distribution tarball, so they are not cleaned here.
+clean distclean maintainer-clean:
+ rm -f lex.backup
+
+
like.o: like.c like_match.c
varlena.o: varlena.c levenshtein.c
PG_RETURN_BYTEA_P(pq_endtypsend(&buf));
}
+/*
+ * Get the type name of a jsonb container.
+ */
+static const char *
+JsonbContainerTypeName(JsonbContainer *jbc)
+{
+ JsonbValue scalar;
+
+ if (JsonbExtractScalar(jbc, &scalar))
+ return JsonbTypeName(&scalar);
+ else if (JsonContainerIsArray(jbc))
+ return "array";
+ else if (JsonContainerIsObject(jbc))
+ return "object";
+ else
+ {
+ elog(ERROR, "invalid jsonb container type: 0x%08x", jbc->header);
+ return "unknown";
+ }
+}
+
+/*
+ * Get the type name of a jsonb value.
+ */
+const char *
+JsonbTypeName(JsonbValue *jbv)
+{
+ switch (jbv->type)
+ {
+ case jbvBinary:
+ return JsonbContainerTypeName(jbv->val.binary.data);
+ case jbvObject:
+ return "object";
+ case jbvArray:
+ return "array";
+ case jbvNumeric:
+ return "number";
+ case jbvString:
+ return "string";
+ case jbvBool:
+ return "boolean";
+ case jbvNull:
+ return "null";
+ default:
+ elog(ERROR, "unrecognized jsonb value type: %d", jbv->type);
+ return "unknown";
+ }
+}
+
/*
* SQL function jsonb_typeof(jsonb) -> text
*
jsonb_typeof(PG_FUNCTION_ARGS)
{
Jsonb *in = PG_GETARG_JSONB_P(0);
- JsonbIterator *it;
- JsonbValue v;
- char *result;
-
- if (JB_ROOT_IS_OBJECT(in))
- result = "object";
- else if (JB_ROOT_IS_ARRAY(in) && !JB_ROOT_IS_SCALAR(in))
- result = "array";
- else
- {
- Assert(JB_ROOT_IS_SCALAR(in));
-
- it = JsonbIteratorInit(&in->root);
-
- /*
- * A root scalar is stored as an array of one element, so we get the
- * array and then its first (and only) member.
- */
- (void) JsonbIteratorNext(&it, &v, true);
- Assert(v.type == jbvArray);
- (void) JsonbIteratorNext(&it, &v, true);
- switch (v.type)
- {
- case jbvNull:
- result = "null";
- break;
- case jbvString:
- result = "string";
- break;
- case jbvNumeric:
- result = "number";
- break;
- case jbvBool:
- result = "boolean";
- break;
- default:
- elog(ERROR, "unknown jsonb scalar type");
- }
- }
+ const char *result = JsonbContainerTypeName(&in->root);
PG_RETURN_TEXT_P(cstring_to_text(result));
}
/*
* Extract scalar value from raw-scalar pseudo-array jsonb.
*/
-static bool
+bool
JsonbExtractScalar(JsonbContainer *jbc, JsonbValue *res)
{
JsonbIterator *it;
break;
case jbvNumeric:
+ /* replace numeric NaN with string "NaN" */
+ if (numeric_is_nan(scalarVal->val.numeric))
+ {
+ appendToBuffer(buffer, "NaN", 3);
+ *jentry = 3;
+ break;
+ }
+
numlen = VARSIZE_ANY(scalarVal->val.numeric);
padlen = padBufferToInt(buffer);
--- /dev/null
+/*-------------------------------------------------------------------------
+ *
+ * jsonpath.c
+ * Input/output and supporting routines for jsonpath
+ *
+ * jsonpath expression is a chain of path items. First path item is $, $var,
+ * literal or arithmetic expression. Subsequent path items are accessors
+ * (.key, .*, [subscripts], [*]), filters (? (predicate)) and methods (.type(),
+ * .size() etc).
+ *
+ * For instance, structure of path items for simple expression:
+ *
+ * $.a[*].type()
+ *
+ * is pretty evident:
+ *
+ * $ => .a => [*] => .type()
+ *
+ * Some path items such as arithmetic operations, predicates or array
+ * subscripts may comprise subtrees. For instance, more complex expression
+ *
+ * ($.a + $[1 to 5, 7] ? (@ > 3).double()).type()
+ *
+ * have following structure of path items:
+ *
+ * + => .type()
+ * ___/ \___
+ * / \
+ * $ => .a $ => [] => ? => .double()
+ * _||_ |
+ * / \ >
+ * to to / \
+ * / \ / @ 3
+ * 1 5 7
+ *
+ * Binary encoding of jsonpath constitutes a sequence of 4-bytes aligned
+ * variable-length path items connected by links. Every item has a header
+ * consisting of item type (enum JsonPathItemType) and offset of next item
+ * (zero means no next item). After the header, item may have payload
+ * depending on item type. For instance, payload of '.key' accessor item is
+ * length of key name and key name itself. Payload of '>' arithmetic operator
+ * item is offsets of right and left operands.
+ *
+ * So, binary representation of sample expression above is:
+ * (bottom arrows are next links, top lines are argument links)
+ *
+ * _____
+ * _____ ___/____ \ __
+ * _ /_ \ _____/__/____ \ \ __ _ /_ \
+ * / / \ \ / / / \ \ \ / \ / / \ \
+ * +(LR) $ .a $ [](* to *, * to *) 1 5 7 ?(A) >(LR) @ 3 .double() .type()
+ * | | ^ | ^| ^| ^ ^
+ * | |__| |__||________________________||___________________| |
+ * |_______________________________________________________________________|
+ *
+ * Copyright (c) 2019, PostgreSQL Global Development Group
+ *
+ * IDENTIFICATION
+ * src/backend/utils/adt/jsonpath.c
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#include "postgres.h"
+
+#include "funcapi.h"
+#include "lib/stringinfo.h"
+#include "libpq/pqformat.h"
+#include "miscadmin.h"
+#include "utils/builtins.h"
+#include "utils/json.h"
+#include "utils/jsonpath.h"
+
+
+static Datum jsonPathFromCstring(char *in, int len);
+static char *jsonPathToCstring(StringInfo out, JsonPath *in,
+ int estimated_len);
+static int flattenJsonPathParseItem(StringInfo buf, JsonPathParseItem *item,
+ int nestingLevel, bool insideArraySubscript);
+static void alignStringInfoInt(StringInfo buf);
+static int32 reserveSpaceForItemPointer(StringInfo buf);
+static void printJsonPathItem(StringInfo buf, JsonPathItem *v, bool inKey,
+ bool printBracketes);
+static int operationPriority(JsonPathItemType op);
+
+
+/**************************** INPUT/OUTPUT ********************************/
+
+/*
+ * jsonpath type input function
+ */
+Datum
+jsonpath_in(PG_FUNCTION_ARGS)
+{
+ char *in = PG_GETARG_CSTRING(0);
+ int len = strlen(in);
+
+ return jsonPathFromCstring(in, len);
+}
+
+/*
+ * jsonpath type recv function
+ *
+ * The type is sent as text in binary mode, so this is almost the same
+ * as the input function, but it's prefixed with a version number so we
+ * can change the binary format sent in future if necessary. For now,
+ * only version 1 is supported.
+ */
+Datum
+jsonpath_recv(PG_FUNCTION_ARGS)
+{
+ StringInfo buf = (StringInfo) PG_GETARG_POINTER(0);
+ int version = pq_getmsgint(buf, 1);
+ char *str;
+ int nbytes;
+
+ if (version == JSONPATH_VERSION)
+ str = pq_getmsgtext(buf, buf->len - buf->cursor, &nbytes);
+ else
+ elog(ERROR, "unsupported jsonpath version number: %d", version);
+
+ return jsonPathFromCstring(str, nbytes);
+}
+
+/*
+ * jsonpath type output function
+ */
+Datum
+jsonpath_out(PG_FUNCTION_ARGS)
+{
+ JsonPath *in = PG_GETARG_JSONPATH_P(0);
+
+ PG_RETURN_CSTRING(jsonPathToCstring(NULL, in, VARSIZE(in)));
+}
+
+/*
+ * jsonpath type send function
+ *
+ * Just send jsonpath as a version number, then a string of text
+ */
+Datum
+jsonpath_send(PG_FUNCTION_ARGS)
+{
+ JsonPath *in = PG_GETARG_JSONPATH_P(0);
+ StringInfoData buf;
+ StringInfoData jtext;
+ int version = JSONPATH_VERSION;
+
+ initStringInfo(&jtext);
+ (void) jsonPathToCstring(&jtext, in, VARSIZE(in));
+
+ pq_begintypsend(&buf);
+ pq_sendint8(&buf, version);
+ pq_sendtext(&buf, jtext.data, jtext.len);
+ pfree(jtext.data);
+
+ PG_RETURN_BYTEA_P(pq_endtypsend(&buf));
+}
+
+/*
+ * Converts C-string to a jsonpath value.
+ *
+ * Uses jsonpath parser to turn string into an AST, then
+ * flattenJsonPathParseItem() does second pass turning AST into binary
+ * representation of jsonpath.
+ */
+static Datum
+jsonPathFromCstring(char *in, int len)
+{
+ JsonPathParseResult *jsonpath = parsejsonpath(in, len);
+ JsonPath *res;
+ StringInfoData buf;
+
+ initStringInfo(&buf);
+ enlargeStringInfo(&buf, 4 * len /* estimation */ );
+
+ appendStringInfoSpaces(&buf, JSONPATH_HDRSZ);
+
+ if (!jsonpath)
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
+ errmsg("invalid input syntax for jsonpath: \"%s\"", in)));
+
+ flattenJsonPathParseItem(&buf, jsonpath->expr, 0, false);
+
+ res = (JsonPath *) buf.data;
+ SET_VARSIZE(res, buf.len);
+ res->header = JSONPATH_VERSION;
+ if (jsonpath->lax)
+ res->header |= JSONPATH_LAX;
+
+ PG_RETURN_JSONPATH_P(res);
+}
+
+/*
+ * Converts jsonpath value to a C-string.
+ *
+ * If 'out' argument is non-null, the resulting C-string is stored inside the
+ * StringBuffer. The resulting string is always returned.
+ */
+static char *
+jsonPathToCstring(StringInfo out, JsonPath *in, int estimated_len)
+{
+ StringInfoData buf;
+ JsonPathItem v;
+
+ if (!out)
+ {
+ out = &buf;
+ initStringInfo(out);
+ }
+ enlargeStringInfo(out, estimated_len);
+
+ if (!(in->header & JSONPATH_LAX))
+ appendBinaryStringInfo(out, "strict ", 7);
+
+ jspInit(&v, in);
+ printJsonPathItem(out, &v, false, true);
+
+ return out->data;
+}
+
+/*
+ * Recursive function converting given jsonpath parse item and all its
+ * children into a binary representation.
+ */
+static int
+flattenJsonPathParseItem(StringInfo buf, JsonPathParseItem *item,
+ int nestingLevel, bool insideArraySubscript)
+{
+ /* position from begining of jsonpath data */
+ int32 pos = buf->len - JSONPATH_HDRSZ;
+ int32 chld;
+ int32 next;
+ int argNestingLevel = 0;
+
+ check_stack_depth();
+ CHECK_FOR_INTERRUPTS();
+
+ appendStringInfoChar(buf, (char) (item->type));
+
+ /*
+ * We align buffer to int32 because a series of int32 values often goes
+ * after the header, and we want to read them directly by dereferencing
+ * int32 pointer (see jspInitByBuffer()).
+ */
+ alignStringInfoInt(buf);
+
+ /*
+ * Reserve space for next item pointer. Actual value will be recorded
+ * later, after next and children items processing.
+ */
+ next = reserveSpaceForItemPointer(buf);
+
+ switch (item->type)
+ {
+ case jpiString:
+ case jpiVariable:
+ case jpiKey:
+ appendBinaryStringInfo(buf, (char *) &item->value.string.len,
+ sizeof(item->value.string.len));
+ appendBinaryStringInfo(buf, item->value.string.val,
+ item->value.string.len);
+ appendStringInfoChar(buf, '\0');
+ break;
+ case jpiNumeric:
+ appendBinaryStringInfo(buf, (char *) item->value.numeric,
+ VARSIZE(item->value.numeric));
+ break;
+ case jpiBool:
+ appendBinaryStringInfo(buf, (char *) &item->value.boolean,
+ sizeof(item->value.boolean));
+ break;
+ case jpiAnd:
+ case jpiOr:
+ case jpiEqual:
+ case jpiNotEqual:
+ case jpiLess:
+ case jpiGreater:
+ case jpiLessOrEqual:
+ case jpiGreaterOrEqual:
+ case jpiAdd:
+ case jpiSub:
+ case jpiMul:
+ case jpiDiv:
+ case jpiMod:
+ case jpiStartsWith:
+ {
+ /*
+ * First, reserve place for left/right arg's positions, then
+ * record both args and sets actual position in reserved
+ * places.
+ */
+ int32 left = reserveSpaceForItemPointer(buf);
+ int32 right = reserveSpaceForItemPointer(buf);
+
+ chld = !item->value.args.left ? pos :
+ flattenJsonPathParseItem(buf, item->value.args.left,
+ nestingLevel + argNestingLevel,
+ insideArraySubscript);
+ *(int32 *) (buf->data + left) = chld - pos;
+
+ chld = !item->value.args.right ? pos :
+ flattenJsonPathParseItem(buf, item->value.args.right,
+ nestingLevel + argNestingLevel,
+ insideArraySubscript);
+ *(int32 *) (buf->data + right) = chld - pos;
+ }
+ break;
+ case jpiLikeRegex:
+ {
+ int32 offs;
+
+ appendBinaryStringInfo(buf,
+ (char *) &item->value.like_regex.flags,
+ sizeof(item->value.like_regex.flags));
+ offs = reserveSpaceForItemPointer(buf);
+ appendBinaryStringInfo(buf,
+ (char *) &item->value.like_regex.patternlen,
+ sizeof(item->value.like_regex.patternlen));
+ appendBinaryStringInfo(buf, item->value.like_regex.pattern,
+ item->value.like_regex.patternlen);
+ appendStringInfoChar(buf, '\0');
+
+ chld = flattenJsonPathParseItem(buf, item->value.like_regex.expr,
+ nestingLevel,
+ insideArraySubscript);
+ *(int32 *) (buf->data + offs) = chld - pos;
+ }
+ break;
+ case jpiFilter:
+ argNestingLevel++;
+ /* fall through */
+ case jpiIsUnknown:
+ case jpiNot:
+ case jpiPlus:
+ case jpiMinus:
+ case jpiExists:
+ {
+ int32 arg = reserveSpaceForItemPointer(buf);
+
+ chld = flattenJsonPathParseItem(buf, item->value.arg,
+ nestingLevel + argNestingLevel,
+ insideArraySubscript);
+ *(int32 *) (buf->data + arg) = chld - pos;
+ }
+ break;
+ case jpiNull:
+ break;
+ case jpiRoot:
+ break;
+ case jpiAnyArray:
+ case jpiAnyKey:
+ break;
+ case jpiCurrent:
+ if (nestingLevel <= 0)
+ ereport(ERROR,
+ (errcode(ERRCODE_SYNTAX_ERROR),
+ errmsg("@ is not allowed in root expressions")));
+ break;
+ case jpiLast:
+ if (!insideArraySubscript)
+ ereport(ERROR,
+ (errcode(ERRCODE_SYNTAX_ERROR),
+ errmsg("LAST is allowed only in array subscripts")));
+ break;
+ case jpiIndexArray:
+ {
+ int32 nelems = item->value.array.nelems;
+ int offset;
+ int i;
+
+ appendBinaryStringInfo(buf, (char *) &nelems, sizeof(nelems));
+
+ offset = buf->len;
+
+ appendStringInfoSpaces(buf, sizeof(int32) * 2 * nelems);
+
+ for (i = 0; i < nelems; i++)
+ {
+ int32 *ppos;
+ int32 topos;
+ int32 frompos =
+ flattenJsonPathParseItem(buf,
+ item->value.array.elems[i].from,
+ nestingLevel, true) - pos;
+
+ if (item->value.array.elems[i].to)
+ topos = flattenJsonPathParseItem(buf,
+ item->value.array.elems[i].to,
+ nestingLevel, true) - pos;
+ else
+ topos = 0;
+
+ ppos = (int32 *) &buf->data[offset + i * 2 * sizeof(int32)];
+
+ ppos[0] = frompos;
+ ppos[1] = topos;
+ }
+ }
+ break;
+ case jpiAny:
+ appendBinaryStringInfo(buf,
+ (char *) &item->value.anybounds.first,
+ sizeof(item->value.anybounds.first));
+ appendBinaryStringInfo(buf,
+ (char *) &item->value.anybounds.last,
+ sizeof(item->value.anybounds.last));
+ break;
+ case jpiType:
+ case jpiSize:
+ case jpiAbs:
+ case jpiFloor:
+ case jpiCeiling:
+ case jpiDouble:
+ case jpiKeyValue:
+ break;
+ default:
+ elog(ERROR, "unrecognized jsonpath item type: %d", item->type);
+ }
+
+ if (item->next)
+ {
+ chld = flattenJsonPathParseItem(buf, item->next, nestingLevel,
+ insideArraySubscript) - pos;
+ *(int32 *) (buf->data + next) = chld;
+ }
+
+ return pos;
+}
+
+/*
+ * Align StringInfo to int by adding zero padding bytes
+ */
+static void
+alignStringInfoInt(StringInfo buf)
+{
+ switch (INTALIGN(buf->len) - buf->len)
+ {
+ case 3:
+ appendStringInfoCharMacro(buf, 0);
+ case 2:
+ appendStringInfoCharMacro(buf, 0);
+ case 1:
+ appendStringInfoCharMacro(buf, 0);
+ default:
+ break;
+ }
+}
+
+/*
+ * Reserve space for int32 JsonPathItem pointer. Now zero pointer is written,
+ * actual value will be recorded at '(int32 *) &buf->data[pos]' later.
+ */
+static int32
+reserveSpaceForItemPointer(StringInfo buf)
+{
+ int32 pos = buf->len;
+ int32 ptr = 0;
+
+ appendBinaryStringInfo(buf, (char *) &ptr, sizeof(ptr));
+
+ return pos;
+}
+
+/*
+ * Prints text representation of given jsonpath item and all its children.
+ */
+static void
+printJsonPathItem(StringInfo buf, JsonPathItem *v, bool inKey,
+ bool printBracketes)
+{
+ JsonPathItem elem;
+ int i;
+
+ check_stack_depth();
+ CHECK_FOR_INTERRUPTS();
+
+ switch (v->type)
+ {
+ case jpiNull:
+ appendStringInfoString(buf, "null");
+ break;
+ case jpiKey:
+ if (inKey)
+ appendStringInfoChar(buf, '.');
+ escape_json(buf, jspGetString(v, NULL));
+ break;
+ case jpiString:
+ escape_json(buf, jspGetString(v, NULL));
+ break;
+ case jpiVariable:
+ appendStringInfoChar(buf, '$');
+ escape_json(buf, jspGetString(v, NULL));
+ break;
+ case jpiNumeric:
+ appendStringInfoString(buf,
+ DatumGetCString(DirectFunctionCall1(numeric_out,
+ PointerGetDatum(jspGetNumeric(v)))));
+ break;
+ case jpiBool:
+ if (jspGetBool(v))
+ appendBinaryStringInfo(buf, "true", 4);
+ else
+ appendBinaryStringInfo(buf, "false", 5);
+ break;
+ case jpiAnd:
+ case jpiOr:
+ case jpiEqual:
+ case jpiNotEqual:
+ case jpiLess:
+ case jpiGreater:
+ case jpiLessOrEqual:
+ case jpiGreaterOrEqual:
+ case jpiAdd:
+ case jpiSub:
+ case jpiMul:
+ case jpiDiv:
+ case jpiMod:
+ case jpiStartsWith:
+ if (printBracketes)
+ appendStringInfoChar(buf, '(');
+ jspGetLeftArg(v, &elem);
+ printJsonPathItem(buf, &elem, false,
+ operationPriority(elem.type) <=
+ operationPriority(v->type));
+ appendStringInfoChar(buf, ' ');
+ appendStringInfoString(buf, jspOperationName(v->type));
+ appendStringInfoChar(buf, ' ');
+ jspGetRightArg(v, &elem);
+ printJsonPathItem(buf, &elem, false,
+ operationPriority(elem.type) <=
+ operationPriority(v->type));
+ if (printBracketes)
+ appendStringInfoChar(buf, ')');
+ break;
+ case jpiLikeRegex:
+ if (printBracketes)
+ appendStringInfoChar(buf, '(');
+
+ jspInitByBuffer(&elem, v->base, v->content.like_regex.expr);
+ printJsonPathItem(buf, &elem, false,
+ operationPriority(elem.type) <=
+ operationPriority(v->type));
+
+ appendBinaryStringInfo(buf, " like_regex ", 12);
+
+ escape_json(buf, v->content.like_regex.pattern);
+
+ if (v->content.like_regex.flags)
+ {
+ appendBinaryStringInfo(buf, " flag \"", 7);
+
+ if (v->content.like_regex.flags & JSP_REGEX_ICASE)
+ appendStringInfoChar(buf, 'i');
+ if (v->content.like_regex.flags & JSP_REGEX_SLINE)
+ appendStringInfoChar(buf, 's');
+ if (v->content.like_regex.flags & JSP_REGEX_MLINE)
+ appendStringInfoChar(buf, 'm');
+ if (v->content.like_regex.flags & JSP_REGEX_WSPACE)
+ appendStringInfoChar(buf, 'x');
+
+ appendStringInfoChar(buf, '"');
+ }
+
+ if (printBracketes)
+ appendStringInfoChar(buf, ')');
+ break;
+ case jpiPlus:
+ case jpiMinus:
+ if (printBracketes)
+ appendStringInfoChar(buf, '(');
+ appendStringInfoChar(buf, v->type == jpiPlus ? '+' : '-');
+ jspGetArg(v, &elem);
+ printJsonPathItem(buf, &elem, false,
+ operationPriority(elem.type) <=
+ operationPriority(v->type));
+ if (printBracketes)
+ appendStringInfoChar(buf, ')');
+ break;
+ case jpiFilter:
+ appendBinaryStringInfo(buf, "?(", 2);
+ jspGetArg(v, &elem);
+ printJsonPathItem(buf, &elem, false, false);
+ appendStringInfoChar(buf, ')');
+ break;
+ case jpiNot:
+ appendBinaryStringInfo(buf, "!(", 2);
+ jspGetArg(v, &elem);
+ printJsonPathItem(buf, &elem, false, false);
+ appendStringInfoChar(buf, ')');
+ break;
+ case jpiIsUnknown:
+ appendStringInfoChar(buf, '(');
+ jspGetArg(v, &elem);
+ printJsonPathItem(buf, &elem, false, false);
+ appendBinaryStringInfo(buf, ") is unknown", 12);
+ break;
+ case jpiExists:
+ appendBinaryStringInfo(buf, "exists (", 8);
+ jspGetArg(v, &elem);
+ printJsonPathItem(buf, &elem, false, false);
+ appendStringInfoChar(buf, ')');
+ break;
+ case jpiCurrent:
+ Assert(!inKey);
+ appendStringInfoChar(buf, '@');
+ break;
+ case jpiRoot:
+ Assert(!inKey);
+ appendStringInfoChar(buf, '$');
+ break;
+ case jpiLast:
+ appendBinaryStringInfo(buf, "last", 4);
+ break;
+ case jpiAnyArray:
+ appendBinaryStringInfo(buf, "[*]", 3);
+ break;
+ case jpiAnyKey:
+ if (inKey)
+ appendStringInfoChar(buf, '.');
+ appendStringInfoChar(buf, '*');
+ break;
+ case jpiIndexArray:
+ appendStringInfoChar(buf, '[');
+ for (i = 0; i < v->content.array.nelems; i++)
+ {
+ JsonPathItem from;
+ JsonPathItem to;
+ bool range = jspGetArraySubscript(v, &from, &to, i);
+
+ if (i)
+ appendStringInfoChar(buf, ',');
+
+ printJsonPathItem(buf, &from, false, false);
+
+ if (range)
+ {
+ appendBinaryStringInfo(buf, " to ", 4);
+ printJsonPathItem(buf, &to, false, false);
+ }
+ }
+ appendStringInfoChar(buf, ']');
+ break;
+ case jpiAny:
+ if (inKey)
+ appendStringInfoChar(buf, '.');
+
+ if (v->content.anybounds.first == 0 &&
+ v->content.anybounds.last == PG_UINT32_MAX)
+ appendBinaryStringInfo(buf, "**", 2);
+ else if (v->content.anybounds.first == v->content.anybounds.last)
+ {
+ if (v->content.anybounds.first == PG_UINT32_MAX)
+ appendStringInfo(buf, "**{last}");
+ else
+ appendStringInfo(buf, "**{%u}",
+ v->content.anybounds.first);
+ }
+ else if (v->content.anybounds.first == PG_UINT32_MAX)
+ appendStringInfo(buf, "**{last to %u}",
+ v->content.anybounds.last);
+ else if (v->content.anybounds.last == PG_UINT32_MAX)
+ appendStringInfo(buf, "**{%u to last}",
+ v->content.anybounds.first);
+ else
+ appendStringInfo(buf, "**{%u to %u}",
+ v->content.anybounds.first,
+ v->content.anybounds.last);
+ break;
+ case jpiType:
+ appendBinaryStringInfo(buf, ".type()", 7);
+ break;
+ case jpiSize:
+ appendBinaryStringInfo(buf, ".size()", 7);
+ break;
+ case jpiAbs:
+ appendBinaryStringInfo(buf, ".abs()", 6);
+ break;
+ case jpiFloor:
+ appendBinaryStringInfo(buf, ".floor()", 8);
+ break;
+ case jpiCeiling:
+ appendBinaryStringInfo(buf, ".ceiling()", 10);
+ break;
+ case jpiDouble:
+ appendBinaryStringInfo(buf, ".double()", 9);
+ break;
+ case jpiKeyValue:
+ appendBinaryStringInfo(buf, ".keyvalue()", 11);
+ break;
+ default:
+ elog(ERROR, "unrecognized jsonpath item type: %d", v->type);
+ }
+
+ if (jspGetNext(v, &elem))
+ printJsonPathItem(buf, &elem, true, true);
+}
+
+const char *
+jspOperationName(JsonPathItemType type)
+{
+ switch (type)
+ {
+ case jpiAnd:
+ return "&&";
+ case jpiOr:
+ return "||";
+ case jpiEqual:
+ return "==";
+ case jpiNotEqual:
+ return "!=";
+ case jpiLess:
+ return "<";
+ case jpiGreater:
+ return ">";
+ case jpiLessOrEqual:
+ return "<=";
+ case jpiGreaterOrEqual:
+ return ">=";
+ case jpiPlus:
+ case jpiAdd:
+ return "+";
+ case jpiMinus:
+ case jpiSub:
+ return "-";
+ case jpiMul:
+ return "*";
+ case jpiDiv:
+ return "/";
+ case jpiMod:
+ return "%";
+ case jpiStartsWith:
+ return "starts with";
+ case jpiLikeRegex:
+ return "like_regex";
+ case jpiType:
+ return "type";
+ case jpiSize:
+ return "size";
+ case jpiKeyValue:
+ return "keyvalue";
+ case jpiDouble:
+ return "double";
+ case jpiAbs:
+ return "abs";
+ case jpiFloor:
+ return "floor";
+ case jpiCeiling:
+ return "ceiling";
+ default:
+ elog(ERROR, "unrecognized jsonpath item type: %d", type);
+ return NULL;
+ }
+}
+
+static int
+operationPriority(JsonPathItemType op)
+{
+ switch (op)
+ {
+ case jpiOr:
+ return 0;
+ case jpiAnd:
+ return 1;
+ case jpiEqual:
+ case jpiNotEqual:
+ case jpiLess:
+ case jpiGreater:
+ case jpiLessOrEqual:
+ case jpiGreaterOrEqual:
+ case jpiStartsWith:
+ return 2;
+ case jpiAdd:
+ case jpiSub:
+ return 3;
+ case jpiMul:
+ case jpiDiv:
+ case jpiMod:
+ return 4;
+ case jpiPlus:
+ case jpiMinus:
+ return 5;
+ default:
+ return 6;
+ }
+}
+
+/******************* Support functions for JsonPath *************************/
+
+/*
+ * Support macros to read stored values
+ */
+
+#define read_byte(v, b, p) do { \
+ (v) = *(uint8*)((b) + (p)); \
+ (p) += 1; \
+} while(0) \
+
+#define read_int32(v, b, p) do { \
+ (v) = *(uint32*)((b) + (p)); \
+ (p) += sizeof(int32); \
+} while(0) \
+
+#define read_int32_n(v, b, p, n) do { \
+ (v) = (void *)((b) + (p)); \
+ (p) += sizeof(int32) * (n); \
+} while(0) \
+
+/*
+ * Read root node and fill root node representation
+ */
+void
+jspInit(JsonPathItem *v, JsonPath *js)
+{
+ Assert((js->header & ~JSONPATH_LAX) == JSONPATH_VERSION);
+ jspInitByBuffer(v, js->data, 0);
+}
+
+/*
+ * Read node from buffer and fill its representation
+ */
+void
+jspInitByBuffer(JsonPathItem *v, char *base, int32 pos)
+{
+ v->base = base + pos;
+
+ read_byte(v->type, base, pos);
+ pos = INTALIGN((uintptr_t) (base + pos)) - (uintptr_t) base;
+ read_int32(v->nextPos, base, pos);
+
+ switch (v->type)
+ {
+ case jpiNull:
+ case jpiRoot:
+ case jpiCurrent:
+ case jpiAnyArray:
+ case jpiAnyKey:
+ case jpiType:
+ case jpiSize:
+ case jpiAbs:
+ case jpiFloor:
+ case jpiCeiling:
+ case jpiDouble:
+ case jpiKeyValue:
+ case jpiLast:
+ break;
+ case jpiKey:
+ case jpiString:
+ case jpiVariable:
+ read_int32(v->content.value.datalen, base, pos);
+ /* follow next */
+ case jpiNumeric:
+ case jpiBool:
+ v->content.value.data = base + pos;
+ break;
+ case jpiAnd:
+ case jpiOr:
+ case jpiAdd:
+ case jpiSub:
+ case jpiMul:
+ case jpiDiv:
+ case jpiMod:
+ case jpiEqual:
+ case jpiNotEqual:
+ case jpiLess:
+ case jpiGreater:
+ case jpiLessOrEqual:
+ case jpiGreaterOrEqual:
+ case jpiStartsWith:
+ read_int32(v->content.args.left, base, pos);
+ read_int32(v->content.args.right, base, pos);
+ break;
+ case jpiLikeRegex:
+ read_int32(v->content.like_regex.flags, base, pos);
+ read_int32(v->content.like_regex.expr, base, pos);
+ read_int32(v->content.like_regex.patternlen, base, pos);
+ v->content.like_regex.pattern = base + pos;
+ break;
+ case jpiNot:
+ case jpiExists:
+ case jpiIsUnknown:
+ case jpiPlus:
+ case jpiMinus:
+ case jpiFilter:
+ read_int32(v->content.arg, base, pos);
+ break;
+ case jpiIndexArray:
+ read_int32(v->content.array.nelems, base, pos);
+ read_int32_n(v->content.array.elems, base, pos,
+ v->content.array.nelems * 2);
+ break;
+ case jpiAny:
+ read_int32(v->content.anybounds.first, base, pos);
+ read_int32(v->content.anybounds.last, base, pos);
+ break;
+ default:
+ elog(ERROR, "unrecognized jsonpath item type: %d", v->type);
+ }
+}
+
+void
+jspGetArg(JsonPathItem *v, JsonPathItem *a)
+{
+ Assert(v->type == jpiFilter ||
+ v->type == jpiNot ||
+ v->type == jpiIsUnknown ||
+ v->type == jpiExists ||
+ v->type == jpiPlus ||
+ v->type == jpiMinus);
+
+ jspInitByBuffer(a, v->base, v->content.arg);
+}
+
+bool
+jspGetNext(JsonPathItem *v, JsonPathItem *a)
+{
+ if (jspHasNext(v))
+ {
+ Assert(v->type == jpiString ||
+ v->type == jpiNumeric ||
+ v->type == jpiBool ||
+ v->type == jpiNull ||
+ v->type == jpiKey ||
+ v->type == jpiAny ||
+ v->type == jpiAnyArray ||
+ v->type == jpiAnyKey ||
+ v->type == jpiIndexArray ||
+ v->type == jpiFilter ||
+ v->type == jpiCurrent ||
+ v->type == jpiExists ||
+ v->type == jpiRoot ||
+ v->type == jpiVariable ||
+ v->type == jpiLast ||
+ v->type == jpiAdd ||
+ v->type == jpiSub ||
+ v->type == jpiMul ||
+ v->type == jpiDiv ||
+ v->type == jpiMod ||
+ v->type == jpiPlus ||
+ v->type == jpiMinus ||
+ v->type == jpiEqual ||
+ v->type == jpiNotEqual ||
+ v->type == jpiGreater ||
+ v->type == jpiGreaterOrEqual ||
+ v->type == jpiLess ||
+ v->type == jpiLessOrEqual ||
+ v->type == jpiAnd ||
+ v->type == jpiOr ||
+ v->type == jpiNot ||
+ v->type == jpiIsUnknown ||
+ v->type == jpiType ||
+ v->type == jpiSize ||
+ v->type == jpiAbs ||
+ v->type == jpiFloor ||
+ v->type == jpiCeiling ||
+ v->type == jpiDouble ||
+ v->type == jpiKeyValue ||
+ v->type == jpiStartsWith);
+
+ if (a)
+ jspInitByBuffer(a, v->base, v->nextPos);
+ return true;
+ }
+
+ return false;
+}
+
+void
+jspGetLeftArg(JsonPathItem *v, JsonPathItem *a)
+{
+ Assert(v->type == jpiAnd ||
+ v->type == jpiOr ||
+ v->type == jpiEqual ||
+ v->type == jpiNotEqual ||
+ v->type == jpiLess ||
+ v->type == jpiGreater ||
+ v->type == jpiLessOrEqual ||
+ v->type == jpiGreaterOrEqual ||
+ v->type == jpiAdd ||
+ v->type == jpiSub ||
+ v->type == jpiMul ||
+ v->type == jpiDiv ||
+ v->type == jpiMod ||
+ v->type == jpiStartsWith);
+
+ jspInitByBuffer(a, v->base, v->content.args.left);
+}
+
+void
+jspGetRightArg(JsonPathItem *v, JsonPathItem *a)
+{
+ Assert(v->type == jpiAnd ||
+ v->type == jpiOr ||
+ v->type == jpiEqual ||
+ v->type == jpiNotEqual ||
+ v->type == jpiLess ||
+ v->type == jpiGreater ||
+ v->type == jpiLessOrEqual ||
+ v->type == jpiGreaterOrEqual ||
+ v->type == jpiAdd ||
+ v->type == jpiSub ||
+ v->type == jpiMul ||
+ v->type == jpiDiv ||
+ v->type == jpiMod ||
+ v->type == jpiStartsWith);
+
+ jspInitByBuffer(a, v->base, v->content.args.right);
+}
+
+bool
+jspGetBool(JsonPathItem *v)
+{
+ Assert(v->type == jpiBool);
+
+ return (bool) *v->content.value.data;
+}
+
+Numeric
+jspGetNumeric(JsonPathItem *v)
+{
+ Assert(v->type == jpiNumeric);
+
+ return (Numeric) v->content.value.data;
+}
+
+char *
+jspGetString(JsonPathItem *v, int32 *len)
+{
+ Assert(v->type == jpiKey ||
+ v->type == jpiString ||
+ v->type == jpiVariable);
+
+ if (len)
+ *len = v->content.value.datalen;
+ return v->content.value.data;
+}
+
+bool
+jspGetArraySubscript(JsonPathItem *v, JsonPathItem *from, JsonPathItem *to,
+ int i)
+{
+ Assert(v->type == jpiIndexArray);
+
+ jspInitByBuffer(from, v->base, v->content.array.elems[i].from);
+
+ if (!v->content.array.elems[i].to)
+ return false;
+
+ jspInitByBuffer(to, v->base, v->content.array.elems[i].to);
+
+ return true;
+}
--- /dev/null
+/*-------------------------------------------------------------------------
+ *
+ * jsonpath_exec.c
+ * Routines for SQL/JSON path execution.
+ *
+ * Jsonpath is executed in the global context stored in JsonPathExecContext,
+ * which is passed to almost every function involved into execution. Entry
+ * point for jsonpath execution is executeJsonPath() function, which
+ * initializes execution context including initial JsonPathItem and JsonbValue,
+ * flags, stack for calculation of @ in filters.
+ *
+ * The result of jsonpath query execution is enum JsonPathExecResult and
+ * if succeeded sequence of JsonbValue, written to JsonValueList *found, which
+ * is passed through the jsonpath items. When found == NULL, we're inside
+ * exists-query and we're interested only in whether result is empty. In this
+ * case execution is stopped once first result item is found, and the only
+ * execution result is JsonPathExecResult. The values of JsonPathExecResult
+ * are following:
+ * - jperOk -- result sequence is not empty
+ * - jperNotFound -- result sequence is empty
+ * - jperError -- error occurred during execution
+ *
+ * Jsonpath is executed recursively (see executeItem()) starting form the
+ * first path item (which in turn might be, for instance, an arithmetic
+ * expression evaluated separately). On each step single JsonbValue obtained
+ * from previous path item is processed. The result of processing is a
+ * sequence of JsonbValue (probably empty), which is passed to the next path
+ * item one by one. When there is no next path item, then JsonbValue is added
+ * to the 'found' list. When found == NULL, then execution functions just
+ * return jperOk (see executeNextItem()).
+ *
+ * Many of jsonpath operations require automatic unwrapping of arrays in lax
+ * mode. So, if input value is array, then corresponding operation is
+ * processed not on array itself, but on all of its members one by one.
+ * executeItemOptUnwrapTarget() function have 'unwrap' argument, which indicates
+ * whether unwrapping of array is needed. When unwrap == true, each of array
+ * members is passed to executeItemOptUnwrapTarget() again but with unwrap == false
+ * in order to evade subsequent array unwrapping.
+ *
+ * All boolean expressions (predicates) are evaluated by executeBoolItem()
+ * function, which returns tri-state JsonPathBool. When error is occurred
+ * during predicate execution, it returns jpbUnknown. According to standard
+ * predicates can be only inside filters. But we support their usage as
+ * jsonpath expression. This helps us to implement @@ operator. In this case
+ * resulting JsonPathBool is transformed into jsonb bool or null.
+ *
+ * Arithmetic and boolean expression are evaluated recursively from expression
+ * tree top down to the leaves. Therefore, for binary arithmetic expressions
+ * we calculate operands first. Then we check that results are numeric
+ * singleton lists, calculate the result and pass it to the next path item.
+ *
+ * Copyright (c) 2019, PostgreSQL Global Development Group
+ *
+ * IDENTIFICATION
+ * src/backend/utils/adt/jsonpath_exec.c
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#include "postgres.h"
+
+#include "catalog/pg_collation.h"
+#include "catalog/pg_type.h"
+#include "funcapi.h"
+#include "lib/stringinfo.h"
+#include "miscadmin.h"
+#include "regex/regex.h"
+#include "utils/builtins.h"
+#include "utils/datum.h"
+#include "utils/formatting.h"
+#include "utils/float.h"
+#include "utils/guc.h"
+#include "utils/json.h"
+#include "utils/jsonpath.h"
+#include "utils/date.h"
+#include "utils/timestamp.h"
+#include "utils/varlena.h"
+
+
+/* Standard error message for SQL/JSON errors */
+#define ERRMSG_JSON_ARRAY_NOT_FOUND "SQL/JSON array not found"
+#define ERRMSG_JSON_OBJECT_NOT_FOUND "SQL/JSON object not found"
+#define ERRMSG_JSON_MEMBER_NOT_FOUND "SQL/JSON member not found"
+#define ERRMSG_JSON_NUMBER_NOT_FOUND "SQL/JSON number not found"
+#define ERRMSG_JSON_SCALAR_REQUIRED "SQL/JSON scalar required"
+#define ERRMSG_SINGLETON_JSON_ITEM_REQUIRED "singleton SQL/JSON item required"
+#define ERRMSG_NON_NUMERIC_JSON_ITEM "non-numeric SQL/JSON item"
+#define ERRMSG_INVALID_JSON_SUBSCRIPT "invalid SQL/JSON subscript"
+
+/*
+ * Represents "base object" and it's "id" for .keyvalue() evaluation.
+ */
+typedef struct JsonBaseObjectInfo
+{
+ JsonbContainer *jbc;
+ int id;
+} JsonBaseObjectInfo;
+
+/*
+ * Context of jsonpath execution.
+ */
+typedef struct JsonPathExecContext
+{
+ Jsonb *vars; /* variables to substitute into jsonpath */
+ JsonbValue *root; /* for $ evaluation */
+ JsonbValue *current; /* for @ evaluation */
+ JsonBaseObjectInfo baseObject; /* "base object" for .keyvalue()
+ * evaluation */
+ int lastGeneratedObjectId; /* "id" counter for .keyvalue()
+ * evaluation */
+ int innermostArraySize; /* for LAST array index evaluation */
+ bool laxMode; /* true for "lax" mode, false for "strict"
+ * mode */
+ bool ignoreStructuralErrors; /* with "true" structural errors such
+ * as absence of required json item or
+ * unexpected json item type are
+ * ignored */
+ bool throwErrors; /* with "false" all suppressible errors are
+ * suppressed */
+} JsonPathExecContext;
+
+/* Context for LIKE_REGEX execution. */
+typedef struct JsonLikeRegexContext
+{
+ text *regex;
+ int cflags;
+} JsonLikeRegexContext;
+
+/* Result of jsonpath predicate evaluation */
+typedef enum JsonPathBool
+{
+ jpbFalse = 0,
+ jpbTrue = 1,
+ jpbUnknown = 2
+} JsonPathBool;
+
+/* Result of jsonpath expression evaluation */
+typedef enum JsonPathExecResult
+{
+ jperOk = 0,
+ jperNotFound = 1,
+ jperError = 2
+} JsonPathExecResult;
+
+#define jperIsError(jper) ((jper) == jperError)
+
+/*
+ * List of jsonb values with shortcut for single-value list.
+ */
+typedef struct JsonValueList
+{
+ JsonbValue *singleton;
+ List *list;
+} JsonValueList;
+
+typedef struct JsonValueListIterator
+{
+ JsonbValue *value;
+ ListCell *next;
+} JsonValueListIterator;
+
+/* strict/lax flags is decomposed into four [un]wrap/error flags */
+#define jspStrictAbsenseOfErrors(cxt) (!(cxt)->laxMode)
+#define jspAutoUnwrap(cxt) ((cxt)->laxMode)
+#define jspAutoWrap(cxt) ((cxt)->laxMode)
+#define jspIgnoreStructuralErrors(cxt) ((cxt)->ignoreStructuralErrors)
+#define jspThrowErrors(cxt) ((cxt)->throwErrors)
+
+/* Convenience macro: return or throw error depending on context */
+#define RETURN_ERROR(throw_error) \
+do { \
+ if (jspThrowErrors(cxt)) \
+ throw_error; \
+ else \
+ return jperError; \
+} while (0)
+
+typedef JsonPathBool (*JsonPathPredicateCallback) (JsonPathItem *jsp,
+ JsonbValue *larg,
+ JsonbValue *rarg,
+ void *param);
+
+static JsonPathExecResult executeJsonPath(JsonPath *path, Jsonb *vars,
+ Jsonb *json, bool throwErrors, JsonValueList *result);
+static JsonPathExecResult executeItem(JsonPathExecContext *cxt,
+ JsonPathItem *jsp, JsonbValue *jb, JsonValueList *found);
+static JsonPathExecResult executeItemOptUnwrapTarget(JsonPathExecContext *cxt,
+ JsonPathItem *jsp, JsonbValue *jb,
+ JsonValueList *found, bool unwrap);
+static JsonPathExecResult executeItemUnwrapTargetArray(JsonPathExecContext *cxt,
+ JsonPathItem *jsp, JsonbValue *jb,
+ JsonValueList *found, bool unwrapElements);
+static JsonPathExecResult executeNextItem(JsonPathExecContext *cxt,
+ JsonPathItem *cur, JsonPathItem *next,
+ JsonbValue *v, JsonValueList *found, bool copy);
+static JsonPathExecResult executeItemOptUnwrapResult(
+ JsonPathExecContext *cxt, JsonPathItem *jsp, JsonbValue *jb,
+ bool unwrap, JsonValueList *found);
+static JsonPathExecResult executeItemOptUnwrapResultNoThrow(
+ JsonPathExecContext *cxt, JsonPathItem *jsp,
+ JsonbValue *jb, bool unwrap, JsonValueList *found);
+static JsonPathBool executeBoolItem(JsonPathExecContext *cxt,
+ JsonPathItem *jsp, JsonbValue *jb, bool canHaveNext);
+static JsonPathBool executeNestedBoolItem(JsonPathExecContext *cxt,
+ JsonPathItem *jsp, JsonbValue *jb);
+static JsonPathExecResult executeAnyItem(JsonPathExecContext *cxt,
+ JsonPathItem *jsp, JsonbContainer *jbc, JsonValueList *found,
+ uint32 level, uint32 first, uint32 last,
+ bool ignoreStructuralErrors, bool unwrapNext);
+static JsonPathBool executePredicate(JsonPathExecContext *cxt,
+ JsonPathItem *pred, JsonPathItem *larg, JsonPathItem *rarg,
+ JsonbValue *jb, bool unwrapRightArg,
+ JsonPathPredicateCallback exec, void *param);
+static JsonPathExecResult executeBinaryArithmExpr(JsonPathExecContext *cxt,
+ JsonPathItem *jsp, JsonbValue *jb, PGFunction func,
+ JsonValueList *found);
+static JsonPathExecResult executeUnaryArithmExpr(JsonPathExecContext *cxt,
+ JsonPathItem *jsp, JsonbValue *jb, PGFunction func,
+ JsonValueList *found);
+static JsonPathBool executeStartsWith(JsonPathItem *jsp,
+ JsonbValue *whole, JsonbValue *initial, void *param);
+static JsonPathBool executeLikeRegex(JsonPathItem *jsp, JsonbValue *str,
+ JsonbValue *rarg, void *param);
+static JsonPathExecResult executeNumericItemMethod(JsonPathExecContext *cxt,
+ JsonPathItem *jsp, JsonbValue *jb, bool unwrap, PGFunction func,
+ JsonValueList *found);
+static JsonPathExecResult executeKeyValueMethod(JsonPathExecContext *cxt,
+ JsonPathItem *jsp, JsonbValue *jb, JsonValueList *found);
+static JsonPathExecResult appendBoolResult(JsonPathExecContext *cxt,
+ JsonPathItem *jsp, JsonValueList *found, JsonPathBool res);
+static void getJsonPathItem(JsonPathExecContext *cxt, JsonPathItem *item,
+ JsonbValue *value);
+static void getJsonPathVariable(JsonPathExecContext *cxt,
+ JsonPathItem *variable, Jsonb *vars, JsonbValue *value);
+static int JsonbArraySize(JsonbValue *jb);
+static JsonPathBool executeComparison(JsonPathItem *cmp, JsonbValue *lv,
+ JsonbValue *rv, void *p);
+static JsonPathBool compareItems(int32 op, JsonbValue *jb1, JsonbValue *jb2);
+static int compareNumeric(Numeric a, Numeric b);
+static JsonbValue *copyJsonbValue(JsonbValue *src);
+static JsonPathExecResult getArrayIndex(JsonPathExecContext *cxt,
+ JsonPathItem *jsp, JsonbValue *jb, int32 *index);
+static JsonBaseObjectInfo setBaseObject(JsonPathExecContext *cxt,
+ JsonbValue *jbv, int32 id);
+static void JsonValueListAppend(JsonValueList *jvl, JsonbValue *jbv);
+static int JsonValueListLength(const JsonValueList *jvl);
+static bool JsonValueListIsEmpty(JsonValueList *jvl);
+static JsonbValue *JsonValueListHead(JsonValueList *jvl);
+static List *JsonValueListGetList(JsonValueList *jvl);
+static void JsonValueListInitIterator(const JsonValueList *jvl,
+ JsonValueListIterator *it);
+static JsonbValue *JsonValueListNext(const JsonValueList *jvl,
+ JsonValueListIterator *it);
+static int JsonbType(JsonbValue *jb);
+static JsonbValue *JsonbInitBinary(JsonbValue *jbv, Jsonb *jb);
+static int JsonbType(JsonbValue *jb);
+static JsonbValue *getScalar(JsonbValue *scalar, enum jbvType type);
+static JsonbValue *wrapItemsInArray(const JsonValueList *items);
+
+/****************** User interface to JsonPath executor ********************/
+
+/*
+ * jsonb_path_exists
+ * Returns true if jsonpath returns at least one item for the specified
+ * jsonb value. This function and jsonb_path_match() are used to
+ * implement @? and @@ operators, which in turn are intended to have an
+ * index support. Thus, it's desirable to make it easier to achieve
+ * consistency between index scan results and sequential scan results.
+ * So, we throw as less errors as possible. Regarding this function,
+ * such behavior also matches behavior of JSON_EXISTS() clause of
+ * SQL/JSON. Regarding jsonb_path_match(), this function doesn't have
+ * an analogy in SQL/JSON, so we define its behavior on our own.
+ */
+Datum
+jsonb_path_exists(PG_FUNCTION_ARGS)
+{
+ Jsonb *jb = PG_GETARG_JSONB_P(0);
+ JsonPath *jp = PG_GETARG_JSONPATH_P(1);
+ JsonPathExecResult res;
+ Jsonb *vars = NULL;
+ bool silent = true;
+
+ if (PG_NARGS() == 4)
+ {
+ vars = PG_GETARG_JSONB_P(2);
+ silent = PG_GETARG_BOOL(3);
+ }
+
+ res = executeJsonPath(jp, vars, jb, !silent, NULL);
+
+ PG_FREE_IF_COPY(jb, 0);
+ PG_FREE_IF_COPY(jp, 1);
+
+ if (jperIsError(res))
+ PG_RETURN_NULL();
+
+ PG_RETURN_BOOL(res == jperOk);
+}
+
+/*
+ * jsonb_path_exists_opr
+ * Implementation of operator "jsonb @? jsonpath" (2-argument version of
+ * jsonb_path_exists()).
+ */
+Datum
+jsonb_path_exists_opr(PG_FUNCTION_ARGS)
+{
+ /* just call the other one -- it can handle both cases */
+ return jsonb_path_exists(fcinfo);
+}
+
+/*
+ * jsonb_path_match
+ * Returns jsonpath predicate result item for the specified jsonb value.
+ * See jsonb_path_exists() comment for details regarding error handling.
+ */
+Datum
+jsonb_path_match(PG_FUNCTION_ARGS)
+{
+ Jsonb *jb = PG_GETARG_JSONB_P(0);
+ JsonPath *jp = PG_GETARG_JSONPATH_P(1);
+ JsonbValue *jbv;
+ JsonValueList found = {0};
+ Jsonb *vars = NULL;
+ bool silent = true;
+
+ if (PG_NARGS() == 4)
+ {
+ vars = PG_GETARG_JSONB_P(2);
+ silent = PG_GETARG_BOOL(3);
+ }
+
+ (void) executeJsonPath(jp, vars, jb, !silent, &found);
+
+ if (JsonValueListLength(&found) < 1)
+ PG_RETURN_NULL();
+
+ jbv = JsonValueListHead(&found);
+
+ PG_FREE_IF_COPY(jb, 0);
+ PG_FREE_IF_COPY(jp, 1);
+
+ if (jbv->type != jbvBool)
+ PG_RETURN_NULL();
+
+ PG_RETURN_BOOL(jbv->val.boolean);
+}
+
+/*
+ * jsonb_path_match_opr
+ * Implementation of operator "jsonb @@ jsonpath" (2-argument version of
+ * jsonb_path_match()).
+ */
+Datum
+jsonb_path_match_opr(PG_FUNCTION_ARGS)
+{
+ /* just call the other one -- it can handle both cases */
+ return jsonb_path_match(fcinfo);
+}
+
+/*
+ * jsonb_path_query
+ * Executes jsonpath for given jsonb document and returns result as
+ * rowset.
+ */
+Datum
+jsonb_path_query(PG_FUNCTION_ARGS)
+{
+ FuncCallContext *funcctx;
+ List *found;
+ JsonbValue *v;
+ ListCell *c;
+
+ if (SRF_IS_FIRSTCALL())
+ {
+ JsonPath *jp;
+ Jsonb *jb;
+ MemoryContext oldcontext;
+ Jsonb *vars;
+ bool silent;
+ JsonValueList found = {0};
+
+ funcctx = SRF_FIRSTCALL_INIT();
+ oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);
+
+ jb = PG_GETARG_JSONB_P_COPY(0);
+ jp = PG_GETARG_JSONPATH_P_COPY(1);
+ vars = PG_GETARG_JSONB_P_COPY(2);
+ silent = PG_GETARG_BOOL(3);
+
+ (void) executeJsonPath(jp, vars, jb, !silent, &found);
+
+ funcctx->user_fctx = JsonValueListGetList(&found);
+
+ MemoryContextSwitchTo(oldcontext);
+ }
+
+ funcctx = SRF_PERCALL_SETUP();
+ found = funcctx->user_fctx;
+
+ c = list_head(found);
+
+ if (c == NULL)
+ SRF_RETURN_DONE(funcctx);
+
+ v = lfirst(c);
+ funcctx->user_fctx = list_delete_first(found);
+
+ SRF_RETURN_NEXT(funcctx, JsonbPGetDatum(JsonbValueToJsonb(v)));
+}
+
+/*
+ * jsonb_path_query_array
+ * Executes jsonpath for given jsonb document and returns result as
+ * jsonb array.
+ */
+Datum
+jsonb_path_query_array(FunctionCallInfo fcinfo)
+{
+ Jsonb *jb = PG_GETARG_JSONB_P(0);
+ JsonPath *jp = PG_GETARG_JSONPATH_P(1);
+ JsonValueList found = {0};
+ Jsonb *vars = PG_GETARG_JSONB_P(2);
+ bool silent = PG_GETARG_BOOL(3);
+
+ (void) executeJsonPath(jp, vars, jb, !silent, &found);
+
+ PG_RETURN_JSONB_P(JsonbValueToJsonb(wrapItemsInArray(&found)));
+}
+
+/*
+ * jsonb_path_query_first
+ * Executes jsonpath for given jsonb document and returns first result
+ * item. If there are no items, NULL returned.
+ */
+Datum
+jsonb_path_query_first(FunctionCallInfo fcinfo)
+{
+ Jsonb *jb = PG_GETARG_JSONB_P(0);
+ JsonPath *jp = PG_GETARG_JSONPATH_P(1);
+ JsonValueList found = {0};
+ Jsonb *vars = PG_GETARG_JSONB_P(2);
+ bool silent = PG_GETARG_BOOL(3);
+
+ (void) executeJsonPath(jp, vars, jb, !silent, &found);
+
+ if (JsonValueListLength(&found) >= 1)
+ PG_RETURN_JSONB_P(JsonbValueToJsonb(JsonValueListHead(&found)));
+ else
+ PG_RETURN_NULL();
+}
+
+/********************Execute functions for JsonPath**************************/
+
+/*
+ * Interface to jsonpath executor
+ *
+ * 'path' - jsonpath to be executed
+ * 'vars' - variables to be substituted to jsonpath
+ * 'json' - target document for jsonpath evaluation
+ * 'throwErrors' - whether we should throw suppressible errors
+ * 'result' - list to store result items into
+ *
+ * Returns an error happens during processing or NULL on no error.
+ *
+ * Note, jsonb and jsonpath values should be avaliable and untoasted during
+ * work because JsonPathItem, JsonbValue and result item could have pointers
+ * into input values. If caller needs to just check if document matches
+ * jsonpath, then it doesn't provide a result arg. In this case executor
+ * works till first positive result and does not check the rest if possible.
+ * In other case it tries to find all the satisfied result items.
+ */
+static JsonPathExecResult
+executeJsonPath(JsonPath *path, Jsonb *vars, Jsonb *json, bool throwErrors,
+ JsonValueList *result)
+{
+ JsonPathExecContext cxt;
+ JsonPathExecResult res;
+ JsonPathItem jsp;
+ JsonbValue jbv;
+
+ jspInit(&jsp, path);
+
+ if (!JsonbExtractScalar(&json->root, &jbv))
+ JsonbInitBinary(&jbv, json);
+
+ if (vars && !JsonContainerIsObject(&vars->root))
+ {
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+ errmsg("jsonb containing jsonpath variables "
+ "is not an object")));
+ }
+
+ cxt.vars = vars;
+ cxt.laxMode = (path->header & JSONPATH_LAX) != 0;
+ cxt.ignoreStructuralErrors = cxt.laxMode;
+ cxt.root = &jbv;
+ cxt.current = &jbv;
+ cxt.baseObject.jbc = NULL;
+ cxt.baseObject.id = 0;
+ cxt.lastGeneratedObjectId = vars ? 2 : 1;
+ cxt.innermostArraySize = -1;
+ cxt.throwErrors = throwErrors;
+
+ if (jspStrictAbsenseOfErrors(&cxt) && !result)
+ {
+ /*
+ * In strict mode we must get a complete list of values to check that
+ * there are no errors at all.
+ */
+ JsonValueList vals = {0};
+
+ res = executeItem(&cxt, &jsp, &jbv, &vals);
+
+ if (jperIsError(res))
+ return res;
+
+ return JsonValueListIsEmpty(&vals) ? jperNotFound : jperOk;
+ }
+
+ res = executeItem(&cxt, &jsp, &jbv, result);
+
+ Assert(!throwErrors || !jperIsError(res));
+
+ return res;
+}
+
+/*
+ * Execute jsonpath with automatic unwrapping of current item in lax mode.
+ */
+static JsonPathExecResult
+executeItem(JsonPathExecContext *cxt, JsonPathItem *jsp,
+ JsonbValue *jb, JsonValueList *found)
+{
+ return executeItemOptUnwrapTarget(cxt, jsp, jb, found, jspAutoUnwrap(cxt));
+}
+
+/*
+ * Main jsonpath executor function: walks on jsonpath structure, finds
+ * relevant parts of jsonb and evaluates expressions over them.
+ * When 'unwrap' is true current SQL/JSON item is unwrapped if it is an array.
+ */
+static JsonPathExecResult
+executeItemOptUnwrapTarget(JsonPathExecContext *cxt, JsonPathItem *jsp,
+ JsonbValue *jb, JsonValueList *found, bool unwrap)
+{
+ JsonPathItem elem;
+ JsonPathExecResult res = jperNotFound;
+ JsonBaseObjectInfo baseObject;
+
+ check_stack_depth();
+ CHECK_FOR_INTERRUPTS();
+
+ switch (jsp->type)
+ {
+ /* all boolean item types: */
+ case jpiAnd:
+ case jpiOr:
+ case jpiNot:
+ case jpiIsUnknown:
+ case jpiEqual:
+ case jpiNotEqual:
+ case jpiLess:
+ case jpiGreater:
+ case jpiLessOrEqual:
+ case jpiGreaterOrEqual:
+ case jpiExists:
+ case jpiStartsWith:
+ case jpiLikeRegex:
+ {
+ JsonPathBool st = executeBoolItem(cxt, jsp, jb, true);
+
+ res = appendBoolResult(cxt, jsp, found, st);
+ break;
+ }
+
+ case jpiKey:
+ if (JsonbType(jb) == jbvObject)
+ {
+ JsonbValue *v;
+ JsonbValue key;
+
+ key.type = jbvString;
+ key.val.string.val = jspGetString(jsp, &key.val.string.len);
+
+ v = findJsonbValueFromContainer(jb->val.binary.data,
+ JB_FOBJECT, &key);
+
+ if (v != NULL)
+ {
+ res = executeNextItem(cxt, jsp, NULL,
+ v, found, false);
+
+ /* free value if it was not added to found list */
+ if (jspHasNext(jsp) || !found)
+ pfree(v);
+ }
+ else if (!jspIgnoreStructuralErrors(cxt))
+ {
+ StringInfoData keybuf;
+ char *keystr;
+
+ Assert(found);
+
+ if (!jspThrowErrors(cxt))
+ return jperError;
+
+ initStringInfo(&keybuf);
+
+ keystr = pnstrdup(key.val.string.val, key.val.string.len);
+ escape_json(&keybuf, keystr);
+
+ ereport(ERROR,
+ (errcode(ERRCODE_JSON_MEMBER_NOT_FOUND), \
+ errmsg(ERRMSG_JSON_MEMBER_NOT_FOUND),
+ errdetail("JSON object does not contain key %s",
+ keybuf.data)));
+ }
+ }
+ else if (unwrap && JsonbType(jb) == jbvArray)
+ return executeItemUnwrapTargetArray(cxt, jsp, jb, found, false);
+ else if (!jspIgnoreStructuralErrors(cxt))
+ {
+ Assert(found);
+ RETURN_ERROR(ereport(ERROR,
+ (errcode(ERRCODE_JSON_MEMBER_NOT_FOUND),
+ errmsg(ERRMSG_JSON_MEMBER_NOT_FOUND),
+ errdetail("jsonpath member accessor can "
+ "only be applied to an object"))));
+ }
+ break;
+
+ case jpiRoot:
+ jb = cxt->root;
+ baseObject = setBaseObject(cxt, jb, 0);
+ res = executeNextItem(cxt, jsp, NULL, jb, found, true);
+ cxt->baseObject = baseObject;
+ break;
+
+ case jpiCurrent:
+ res = executeNextItem(cxt, jsp, NULL, cxt->current,
+ found, true);
+ break;
+
+ case jpiAnyArray:
+ if (JsonbType(jb) == jbvArray)
+ {
+ bool hasNext = jspGetNext(jsp, &elem);
+
+ res = executeItemUnwrapTargetArray(cxt, hasNext ? &elem : NULL,
+ jb, found, jspAutoUnwrap(cxt));
+ }
+ else if (jspAutoWrap(cxt))
+ res = executeNextItem(cxt, jsp, NULL, jb, found, true);
+ else if (!jspIgnoreStructuralErrors(cxt))
+ RETURN_ERROR(ereport(ERROR,
+ (errcode(ERRCODE_JSON_ARRAY_NOT_FOUND),
+ errmsg(ERRMSG_JSON_ARRAY_NOT_FOUND),
+ errdetail("jsonpath wildcard array accessor "
+ "can only be applied to an array"))));
+ break;
+
+ case jpiIndexArray:
+ if (JsonbType(jb) == jbvArray || jspAutoWrap(cxt))
+ {
+ int innermostArraySize = cxt->innermostArraySize;
+ int i;
+ int size = JsonbArraySize(jb);
+ bool singleton = size < 0;
+ bool hasNext = jspGetNext(jsp, &elem);
+
+ if (singleton)
+ size = 1;
+
+ cxt->innermostArraySize = size; /* for LAST evaluation */
+
+ for (i = 0; i < jsp->content.array.nelems; i++)
+ {
+ JsonPathItem from;
+ JsonPathItem to;
+ int32 index;
+ int32 index_from;
+ int32 index_to;
+ bool range = jspGetArraySubscript(jsp, &from,
+ &to, i);
+
+ res = getArrayIndex(cxt, &from, jb, &index_from);
+
+ if (jperIsError(res))
+ break;
+
+ if (range)
+ {
+ res = getArrayIndex(cxt, &to, jb, &index_to);
+
+ if (jperIsError(res))
+ break;
+ }
+ else
+ index_to = index_from;
+
+ if (!jspIgnoreStructuralErrors(cxt) &&
+ (index_from < 0 ||
+ index_from > index_to ||
+ index_to >= size))
+ RETURN_ERROR(ereport(ERROR,
+ (errcode(ERRCODE_INVALID_JSON_SUBSCRIPT),
+ errmsg(ERRMSG_INVALID_JSON_SUBSCRIPT),
+ errdetail("jsonpath array subscript is "
+ "out of bounds"))));
+
+ if (index_from < 0)
+ index_from = 0;
+
+ if (index_to >= size)
+ index_to = size - 1;
+
+ res = jperNotFound;
+
+ for (index = index_from; index <= index_to; index++)
+ {
+ JsonbValue *v;
+ bool copy;
+
+ if (singleton)
+ {
+ v = jb;
+ copy = true;
+ }
+ else
+ {
+ v = getIthJsonbValueFromContainer(jb->val.binary.data,
+ (uint32) index);
+
+ if (v == NULL)
+ continue;
+
+ copy = false;
+ }
+
+ if (!hasNext && !found)
+ return jperOk;
+
+ res = executeNextItem(cxt, jsp, &elem, v, found,
+ copy);
+
+ if (jperIsError(res))
+ break;
+
+ if (res == jperOk && !found)
+ break;
+ }
+
+ if (jperIsError(res))
+ break;
+
+ if (res == jperOk && !found)
+ break;
+ }
+
+ cxt->innermostArraySize = innermostArraySize;
+ }
+ else if (!jspIgnoreStructuralErrors(cxt))
+ {
+ RETURN_ERROR(ereport(ERROR,
+ (errcode(ERRCODE_JSON_ARRAY_NOT_FOUND),
+ errmsg(ERRMSG_JSON_ARRAY_NOT_FOUND),
+ errdetail("jsonpath array accessor can "
+ "only be applied to an array"))));
+ }
+ break;
+
+ case jpiLast:
+ {
+ JsonbValue tmpjbv;
+ JsonbValue *lastjbv;
+ int last;
+ bool hasNext = jspGetNext(jsp, &elem);
+
+ if (cxt->innermostArraySize < 0)
+ elog(ERROR, "evaluating jsonpath LAST outside of "
+ "array subscript");
+
+ if (!hasNext && !found)
+ {
+ res = jperOk;
+ break;
+ }
+
+ last = cxt->innermostArraySize - 1;
+
+ lastjbv = hasNext ? &tmpjbv : palloc(sizeof(*lastjbv));
+
+ lastjbv->type = jbvNumeric;
+ lastjbv->val.numeric =
+ DatumGetNumeric(DirectFunctionCall1(int4_numeric,
+ Int32GetDatum(last)));
+
+ res = executeNextItem(cxt, jsp, &elem,
+ lastjbv, found, hasNext);
+ }
+ break;
+
+ case jpiAnyKey:
+ if (JsonbType(jb) == jbvObject)
+ {
+ bool hasNext = jspGetNext(jsp, &elem);
+
+ if (jb->type != jbvBinary)
+ elog(ERROR, "invalid jsonb object type: %d", jb->type);
+
+ return executeAnyItem
+ (cxt, hasNext ? &elem : NULL,
+ jb->val.binary.data, found, 1, 1, 1,
+ false, jspAutoUnwrap(cxt));
+ }
+ else if (unwrap && JsonbType(jb) == jbvArray)
+ return executeItemUnwrapTargetArray(cxt, jsp, jb, found, false);
+ else if (!jspIgnoreStructuralErrors(cxt))
+ {
+ Assert(found);
+ RETURN_ERROR(ereport(ERROR,
+ (errcode(ERRCODE_JSON_OBJECT_NOT_FOUND),
+ errmsg(ERRMSG_JSON_OBJECT_NOT_FOUND),
+ errdetail("jsonpath wildcard member accessor "
+ "can only be applied to an object"))));
+ }
+ break;
+
+ case jpiAdd:
+ return executeBinaryArithmExpr(cxt, jsp, jb,
+ numeric_add, found);
+
+ case jpiSub:
+ return executeBinaryArithmExpr(cxt, jsp, jb,
+ numeric_sub, found);
+
+ case jpiMul:
+ return executeBinaryArithmExpr(cxt, jsp, jb,
+ numeric_mul, found);
+
+ case jpiDiv:
+ return executeBinaryArithmExpr(cxt, jsp, jb,
+ numeric_div, found);
+
+ case jpiMod:
+ return executeBinaryArithmExpr(cxt, jsp, jb,
+ numeric_mod, found);
+
+ case jpiPlus:
+ return executeUnaryArithmExpr(cxt, jsp, jb, NULL, found);
+
+ case jpiMinus:
+ return executeUnaryArithmExpr(cxt, jsp, jb, numeric_uminus,
+ found);
+
+ case jpiFilter:
+ {
+ JsonPathBool st;
+
+ if (unwrap && JsonbType(jb) == jbvArray)
+ return executeItemUnwrapTargetArray(cxt, jsp, jb, found,
+ false);
+
+ jspGetArg(jsp, &elem);
+ st = executeNestedBoolItem(cxt, &elem, jb);
+ if (st != jpbTrue)
+ res = jperNotFound;
+ else
+ res = executeNextItem(cxt, jsp, NULL,
+ jb, found, true);
+ break;
+ }
+
+ case jpiAny:
+ {
+ bool hasNext = jspGetNext(jsp, &elem);
+
+ /* first try without any intermediate steps */
+ if (jsp->content.anybounds.first == 0)
+ {
+ bool savedIgnoreStructuralErrors;
+
+ savedIgnoreStructuralErrors = cxt->ignoreStructuralErrors;
+ cxt->ignoreStructuralErrors = true;
+ res = executeNextItem(cxt, jsp, &elem,
+ jb, found, true);
+ cxt->ignoreStructuralErrors = savedIgnoreStructuralErrors;
+
+ if (res == jperOk && !found)
+ break;
+ }
+
+ if (jb->type == jbvBinary)
+ res = executeAnyItem
+ (cxt, hasNext ? &elem : NULL,
+ jb->val.binary.data, found,
+ 1,
+ jsp->content.anybounds.first,
+ jsp->content.anybounds.last,
+ true, jspAutoUnwrap(cxt));
+ break;
+ }
+
+ case jpiNull:
+ case jpiBool:
+ case jpiNumeric:
+ case jpiString:
+ case jpiVariable:
+ {
+ JsonbValue vbuf;
+ JsonbValue *v;
+ bool hasNext = jspGetNext(jsp, &elem);
+
+ if (!hasNext && !found)
+ {
+ res = jperOk; /* skip evaluation */
+ break;
+ }
+
+ v = hasNext ? &vbuf : palloc(sizeof(*v));
+
+ baseObject = cxt->baseObject;
+ getJsonPathItem(cxt, jsp, v);
+
+ res = executeNextItem(cxt, jsp, &elem,
+ v, found, hasNext);
+ cxt->baseObject = baseObject;
+ }
+ break;
+
+ case jpiType:
+ {
+ JsonbValue *jbv = palloc(sizeof(*jbv));
+
+ jbv->type = jbvString;
+ jbv->val.string.val = pstrdup(JsonbTypeName(jb));
+ jbv->val.string.len = strlen(jbv->val.string.val);
+
+ res = executeNextItem(cxt, jsp, NULL, jbv,
+ found, false);
+ }
+ break;
+
+ case jpiSize:
+ {
+ int size = JsonbArraySize(jb);
+
+ if (size < 0)
+ {
+ if (!jspAutoWrap(cxt))
+ {
+ if (!jspIgnoreStructuralErrors(cxt))
+ RETURN_ERROR(ereport(ERROR,
+ (errcode(ERRCODE_JSON_ARRAY_NOT_FOUND),
+ errmsg(ERRMSG_JSON_ARRAY_NOT_FOUND),
+ errdetail("jsonpath item method .%s() "
+ "can only be applied to an array",
+ jspOperationName(jsp->type)))));
+ break;
+ }
+
+ size = 1;
+ }
+
+ jb = palloc(sizeof(*jb));
+
+ jb->type = jbvNumeric;
+ jb->val.numeric =
+ DatumGetNumeric(DirectFunctionCall1(int4_numeric,
+ Int32GetDatum(size)));
+
+ res = executeNextItem(cxt, jsp, NULL, jb, found, false);
+ }
+ break;
+
+ case jpiAbs:
+ return executeNumericItemMethod(cxt, jsp, jb, unwrap, numeric_abs,
+ found);
+
+ case jpiFloor:
+ return executeNumericItemMethod(cxt, jsp, jb, unwrap, numeric_floor,
+ found);
+
+ case jpiCeiling:
+ return executeNumericItemMethod(cxt, jsp, jb, unwrap, numeric_ceil,
+ found);
+
+ case jpiDouble:
+ {
+ JsonbValue jbv;
+
+ if (unwrap && JsonbType(jb) == jbvArray)
+ return executeItemUnwrapTargetArray(cxt, jsp, jb, found,
+ false);
+
+ if (jb->type == jbvNumeric)
+ {
+ char *tmp = DatumGetCString(DirectFunctionCall1(numeric_out,
+ NumericGetDatum(jb->val.numeric)));
+
+ (void) float8in_internal(tmp,
+ NULL,
+ "double precision",
+ tmp);
+
+ res = jperOk;
+ }
+ else if (jb->type == jbvString)
+ {
+ /* cast string as double */
+ double val;
+ char *tmp = pnstrdup(jb->val.string.val,
+ jb->val.string.len);
+
+ val = float8in_internal(tmp,
+ NULL,
+ "double precision",
+ tmp);
+
+ if (isinf(val))
+ RETURN_ERROR(ereport(ERROR,
+ (errcode(ERRCODE_NON_NUMERIC_JSON_ITEM),
+ errmsg(ERRMSG_NON_NUMERIC_JSON_ITEM),
+ errdetail("jsonpath item method .%s() can "
+ "only be applied to a numeric value",
+ jspOperationName(jsp->type)))));
+
+ jb = &jbv;
+ jb->type = jbvNumeric;
+ jb->val.numeric = DatumGetNumeric(DirectFunctionCall1(float8_numeric,
+ Float8GetDatum(val)));
+ res = jperOk;
+ }
+
+ if (res == jperNotFound)
+ RETURN_ERROR(ereport(ERROR,
+ (errcode(ERRCODE_NON_NUMERIC_JSON_ITEM),
+ errmsg(ERRMSG_NON_NUMERIC_JSON_ITEM),
+ errdetail("jsonpath item method .%s() "
+ "can only be applied to a "
+ "string or numeric value",
+ jspOperationName(jsp->type)))));
+
+ res = executeNextItem(cxt, jsp, NULL, jb, found, true);
+ }
+ break;
+
+ case jpiKeyValue:
+ if (unwrap && JsonbType(jb) == jbvArray)
+ return executeItemUnwrapTargetArray(cxt, jsp, jb, found, false);
+
+ return executeKeyValueMethod(cxt, jsp, jb, found);
+
+ default:
+ elog(ERROR, "unrecognized jsonpath item type: %d", jsp->type);
+ }
+
+ return res;
+}
+
+/*
+ * Unwrap current array item and execute jsonpath for each of its elements.
+ */
+static JsonPathExecResult
+executeItemUnwrapTargetArray(JsonPathExecContext *cxt, JsonPathItem *jsp,
+ JsonbValue *jb, JsonValueList *found,
+ bool unwrapElements)
+{
+ if (jb->type != jbvBinary)
+ {
+ Assert(jb->type != jbvArray);
+ elog(ERROR, "invalid jsonb array value type: %d", jb->type);
+ }
+
+ return executeAnyItem
+ (cxt, jsp, jb->val.binary.data, found, 1, 1, 1,
+ false, unwrapElements);
+}
+
+/*
+ * Execute next jsonpath item if exists. Otherwise put "v" to the "found"
+ * list if provided.
+ */
+static JsonPathExecResult
+executeNextItem(JsonPathExecContext *cxt,
+ JsonPathItem *cur, JsonPathItem *next,
+ JsonbValue *v, JsonValueList *found, bool copy)
+{
+ JsonPathItem elem;
+ bool hasNext;
+
+ if (!cur)
+ hasNext = next != NULL;
+ else if (next)
+ hasNext = jspHasNext(cur);
+ else
+ {
+ next = &elem;
+ hasNext = jspGetNext(cur, next);
+ }
+
+ if (hasNext)
+ return executeItem(cxt, next, v, found);
+
+ if (found)
+ JsonValueListAppend(found, copy ? copyJsonbValue(v) : v);
+
+ return jperOk;
+}
+
+/*
+ * Same as executeItem(), but when "unwrap == true" automatically unwraps
+ * each array item from the resulting sequence in lax mode.
+ */
+static JsonPathExecResult
+executeItemOptUnwrapResult(JsonPathExecContext *cxt, JsonPathItem *jsp,
+ JsonbValue *jb, bool unwrap,
+ JsonValueList *found)
+{
+ if (unwrap && jspAutoUnwrap(cxt))
+ {
+ JsonValueList seq = {0};
+ JsonValueListIterator it;
+ JsonPathExecResult res = executeItem(cxt, jsp, jb, &seq);
+ JsonbValue *item;
+
+ if (jperIsError(res))
+ return res;
+
+ JsonValueListInitIterator(&seq, &it);
+ while ((item = JsonValueListNext(&seq, &it)))
+ {
+ Assert(item->type != jbvArray);
+
+ if (JsonbType(item) == jbvArray)
+ executeItemUnwrapTargetArray(cxt, NULL, item, found, false);
+ else
+ JsonValueListAppend(found, item);
+ }
+
+ return jperOk;
+ }
+
+ return executeItem(cxt, jsp, jb, found);
+}
+
+/*
+ * Same as executeItemOptUnwrapResult(), but with error suppression.
+ */
+static JsonPathExecResult
+executeItemOptUnwrapResultNoThrow(JsonPathExecContext *cxt,
+ JsonPathItem *jsp,
+ JsonbValue *jb, bool unwrap,
+ JsonValueList *found)
+{
+ JsonPathExecResult res;
+ bool throwErrors = cxt->throwErrors;
+
+ cxt->throwErrors = false;
+ res = executeItemOptUnwrapResult(cxt, jsp, jb, unwrap, found);
+ cxt->throwErrors = throwErrors;
+
+ return res;
+}
+
+/* Execute boolean-valued jsonpath expression. */
+static JsonPathBool
+executeBoolItem(JsonPathExecContext *cxt, JsonPathItem *jsp,
+ JsonbValue *jb, bool canHaveNext)
+{
+ JsonPathItem larg;
+ JsonPathItem rarg;
+ JsonPathBool res;
+ JsonPathBool res2;
+
+ if (!canHaveNext && jspHasNext(jsp))
+ elog(ERROR, "boolean jsonpath item cannot have next item");
+
+ switch (jsp->type)
+ {
+ case jpiAnd:
+ jspGetLeftArg(jsp, &larg);
+ res = executeBoolItem(cxt, &larg, jb, false);
+
+ if (res == jpbFalse)
+ return jpbFalse;
+
+ /*
+ * SQL/JSON says that we should check second arg in case of
+ * jperError
+ */
+
+ jspGetRightArg(jsp, &rarg);
+ res2 = executeBoolItem(cxt, &rarg, jb, false);
+
+ return res2 == jpbTrue ? res : res2;
+
+ case jpiOr:
+ jspGetLeftArg(jsp, &larg);
+ res = executeBoolItem(cxt, &larg, jb, false);
+
+ if (res == jpbTrue)
+ return jpbTrue;
+
+ jspGetRightArg(jsp, &rarg);
+ res2 = executeBoolItem(cxt, &rarg, jb, false);
+
+ return res2 == jpbFalse ? res : res2;
+
+ case jpiNot:
+ jspGetArg(jsp, &larg);
+
+ res = executeBoolItem(cxt, &larg, jb, false);
+
+ if (res == jpbUnknown)
+ return jpbUnknown;
+
+ return res == jpbTrue ? jpbFalse : jpbTrue;
+
+ case jpiIsUnknown:
+ jspGetArg(jsp, &larg);
+ res = executeBoolItem(cxt, &larg, jb, false);
+ return res == jpbUnknown ? jpbTrue : jpbFalse;
+
+ case jpiEqual:
+ case jpiNotEqual:
+ case jpiLess:
+ case jpiGreater:
+ case jpiLessOrEqual:
+ case jpiGreaterOrEqual:
+ jspGetLeftArg(jsp, &larg);
+ jspGetRightArg(jsp, &rarg);
+ return executePredicate(cxt, jsp, &larg, &rarg, jb, true,
+ executeComparison, NULL);
+
+ case jpiStartsWith: /* 'whole STARTS WITH initial' */
+ jspGetLeftArg(jsp, &larg); /* 'whole' */
+ jspGetRightArg(jsp, &rarg); /* 'initial' */
+ return executePredicate(cxt, jsp, &larg, &rarg, jb, false,
+ executeStartsWith, NULL);
+
+ case jpiLikeRegex: /* 'expr LIKE_REGEX pattern FLAGS flags' */
+ {
+ /*
+ * 'expr' is a sequence-returning expression. 'pattern' is a
+ * regex string literal. SQL/JSON standard requires XQuery
+ * regexes, but we use Postgres regexes here. 'flags' is a
+ * string literal converted to integer flags at compile-time.
+ */
+ JsonLikeRegexContext lrcxt = {0};
+
+ jspInitByBuffer(&larg, jsp->base,
+ jsp->content.like_regex.expr);
+
+ return executePredicate(cxt, jsp, &larg, NULL, jb, false,
+ executeLikeRegex, &lrcxt);
+ }
+
+ case jpiExists:
+ jspGetArg(jsp, &larg);
+
+ if (jspStrictAbsenseOfErrors(cxt))
+ {
+ /*
+ * In strict mode we must get a complete list of values to
+ * check that there are no errors at all.
+ */
+ JsonValueList vals = {0};
+ JsonPathExecResult res =
+ executeItemOptUnwrapResultNoThrow(cxt, &larg, jb,
+ false, &vals);
+
+ if (jperIsError(res))
+ return jpbUnknown;
+
+ return JsonValueListIsEmpty(&vals) ? jpbFalse : jpbTrue;
+ }
+ else
+ {
+ JsonPathExecResult res =
+ executeItemOptUnwrapResultNoThrow(cxt, &larg, jb,
+ false, NULL);
+
+ if (jperIsError(res))
+ return jpbUnknown;
+
+ return res == jperOk ? jpbTrue : jpbFalse;
+ }
+
+ default:
+ elog(ERROR, "invalid boolean jsonpath item type: %d", jsp->type);
+ return jpbUnknown;
+ }
+}
+
+/*
+ * Execute nested (filters etc.) boolean expression pushing current SQL/JSON
+ * item onto the stack.
+ */
+static JsonPathBool
+executeNestedBoolItem(JsonPathExecContext *cxt, JsonPathItem *jsp,
+ JsonbValue *jb)
+{
+ JsonbValue *prev;
+ JsonPathBool res;
+
+ prev = cxt->current;
+ cxt->current = jb;
+ res = executeBoolItem(cxt, jsp, jb, false);
+ cxt->current = prev;
+
+ return res;
+}
+
+/*
+ * Implementation of several jsonpath nodes:
+ * - jpiAny (.** accessor),
+ * - jpiAnyKey (.* accessor),
+ * - jpiAnyArray ([*] accessor)
+ */
+static JsonPathExecResult
+executeAnyItem(JsonPathExecContext *cxt, JsonPathItem *jsp, JsonbContainer *jbc,
+ JsonValueList *found, uint32 level, uint32 first, uint32 last,
+ bool ignoreStructuralErrors, bool unwrapNext)
+{
+ JsonPathExecResult res = jperNotFound;
+ JsonbIterator *it;
+ int32 r;
+ JsonbValue v;
+
+ check_stack_depth();
+
+ if (level > last)
+ return res;
+
+ it = JsonbIteratorInit(jbc);
+
+ /*
+ * Recursively iterate over jsonb objects/arrays
+ */
+ while ((r = JsonbIteratorNext(&it, &v, true)) != WJB_DONE)
+ {
+ if (r == WJB_KEY)
+ {
+ r = JsonbIteratorNext(&it, &v, true);
+ Assert(r == WJB_VALUE);
+ }
+
+ if (r == WJB_VALUE || r == WJB_ELEM)
+ {
+
+ if (level >= first ||
+ (first == PG_UINT32_MAX && last == PG_UINT32_MAX &&
+ v.type != jbvBinary)) /* leaves only requested */
+ {
+ /* check expression */
+ if (jsp)
+ {
+ if (ignoreStructuralErrors)
+ {
+ bool savedIgnoreStructuralErrors;
+
+ savedIgnoreStructuralErrors = cxt->ignoreStructuralErrors;
+ cxt->ignoreStructuralErrors = true;
+ res = executeItemOptUnwrapTarget(cxt, jsp, &v, found, unwrapNext);
+ cxt->ignoreStructuralErrors = savedIgnoreStructuralErrors;
+ }
+ else
+ res = executeItemOptUnwrapTarget(cxt, jsp, &v, found, unwrapNext);
+
+ if (jperIsError(res))
+ break;
+
+ if (res == jperOk && !found)
+ break;
+ }
+ else if (found)
+ JsonValueListAppend(found, copyJsonbValue(&v));
+ else
+ return jperOk;
+ }
+
+ if (level < last && v.type == jbvBinary)
+ {
+ res = executeAnyItem
+ (cxt, jsp, v.val.binary.data, found,
+ level + 1, first, last,
+ ignoreStructuralErrors, unwrapNext);
+
+ if (jperIsError(res))
+ break;
+
+ if (res == jperOk && found == NULL)
+ break;
+ }
+ }
+ }
+
+ return res;
+}
+
+/*
+ * Execute unary or binary predicate.
+ *
+ * Predicates have existence semantics, because their operands are item
+ * sequences. Pairs of items from the left and right operand's sequences are
+ * checked. TRUE returned only if any pair satisfying the condition is found.
+ * In strict mode, even if the desired pair has already been found, all pairs
+ * still need to be examined to check the absence of errors. If any error
+ * occurs, UNKNOWN (analogous to SQL NULL) is returned.
+ */
+static JsonPathBool
+executePredicate(JsonPathExecContext *cxt, JsonPathItem *pred,
+ JsonPathItem *larg, JsonPathItem *rarg, JsonbValue *jb,
+ bool unwrapRightArg, JsonPathPredicateCallback exec,
+ void *param)
+{
+ JsonPathExecResult res;
+ JsonValueListIterator lseqit;
+ JsonValueList lseq = {0};
+ JsonValueList rseq = {0};
+ JsonbValue *lval;
+ bool error = false;
+ bool found = false;
+
+ /* Left argument is always auto-unwrapped. */
+ res = executeItemOptUnwrapResultNoThrow(cxt, larg, jb, true, &lseq);
+ if (jperIsError(res))
+ return jpbUnknown;
+
+ if (rarg)
+ {
+ /* Right argument is conditionally auto-unwrapped. */
+ res = executeItemOptUnwrapResultNoThrow(cxt, rarg, jb,
+ unwrapRightArg, &rseq);
+ if (jperIsError(res))
+ return jpbUnknown;
+ }
+
+ JsonValueListInitIterator(&lseq, &lseqit);
+ while ((lval = JsonValueListNext(&lseq, &lseqit)))
+ {
+ JsonValueListIterator rseqit;
+ JsonbValue *rval;
+ bool first = true;
+
+ if (rarg)
+ {
+ JsonValueListInitIterator(&rseq, &rseqit);
+ rval = JsonValueListNext(&rseq, &rseqit);
+ }
+ else
+ {
+ rval = NULL;
+ }
+
+ /* Loop over right arg sequence or do single pass otherwise */
+ while (rarg ? (rval != NULL) : first)
+ {
+ JsonPathBool res = exec(pred, lval, rval, param);
+
+ if (res == jpbUnknown)
+ {
+ if (jspStrictAbsenseOfErrors(cxt))
+ return jpbUnknown;
+
+ error = true;
+ }
+ else if (res == jpbTrue)
+ {
+ if (!jspStrictAbsenseOfErrors(cxt))
+ return jpbTrue;
+
+ found = true;
+ }
+
+ first = false;
+ if (rarg)
+ rval = JsonValueListNext(&rseq, &rseqit);
+ }
+ }
+
+ if (found) /* possible only in strict mode */
+ return jpbTrue;
+
+ if (error) /* possible only in lax mode */
+ return jpbUnknown;
+
+ return jpbFalse;
+}
+
+/*
+ * Execute binary arithmetic expression on singleton numeric operands.
+ * Array operands are automatically unwrapped in lax mode.
+ */
+static JsonPathExecResult
+executeBinaryArithmExpr(JsonPathExecContext *cxt, JsonPathItem *jsp,
+ JsonbValue *jb, PGFunction func,
+ JsonValueList *found)
+{
+ JsonPathExecResult jper;
+ JsonPathItem elem;
+ JsonValueList lseq = {0};
+ JsonValueList rseq = {0};
+ JsonbValue *lval;
+ JsonbValue *rval;
+ Datum res;
+
+ jspGetLeftArg(jsp, &elem);
+
+ /*
+ * XXX: By standard only operands of multiplicative expressions are
+ * unwrapped. We extend it to other binary arithmetics expressions too.
+ */
+ jper = executeItemOptUnwrapResult(cxt, &elem, jb, true, &lseq);
+ if (jperIsError(jper))
+ return jper;
+
+ jspGetRightArg(jsp, &elem);
+
+ jper = executeItemOptUnwrapResult(cxt, &elem, jb, true, &rseq);
+ if (jperIsError(jper))
+ return jper;
+
+ if (JsonValueListLength(&lseq) != 1 ||
+ !(lval = getScalar(JsonValueListHead(&lseq), jbvNumeric)))
+ RETURN_ERROR(ereport(ERROR,
+ (errcode(ERRCODE_SINGLETON_JSON_ITEM_REQUIRED),
+ errmsg(ERRMSG_SINGLETON_JSON_ITEM_REQUIRED),
+ errdetail("left operand of binary jsonpath operator %s "
+ "is not a singleton numeric value",
+ jspOperationName(jsp->type)))));
+
+ if (JsonValueListLength(&rseq) != 1 ||
+ !(rval = getScalar(JsonValueListHead(&rseq), jbvNumeric)))
+ RETURN_ERROR(ereport(ERROR,
+ (errcode(ERRCODE_SINGLETON_JSON_ITEM_REQUIRED),
+ errmsg(ERRMSG_SINGLETON_JSON_ITEM_REQUIRED),
+ errdetail("right operand of binary jsonpath operator %s "
+ "is not a singleton numeric value",
+ jspOperationName(jsp->type)))));
+
+ res = DirectFunctionCall2(func,
+ NumericGetDatum(lval->val.numeric),
+ NumericGetDatum(rval->val.numeric));
+
+ if (!jspGetNext(jsp, &elem) && !found)
+ return jperOk;
+
+ lval = palloc(sizeof(*lval));
+ lval->type = jbvNumeric;
+ lval->val.numeric = DatumGetNumeric(res);
+
+ return executeNextItem(cxt, jsp, &elem, lval, found, false);
+}
+
+/*
+ * Execute unary arithmetic expression for each numeric item in its operand's
+ * sequence. Array operand is automatically unwrapped in lax mode.
+ */
+static JsonPathExecResult
+executeUnaryArithmExpr(JsonPathExecContext *cxt, JsonPathItem *jsp,
+ JsonbValue *jb, PGFunction func, JsonValueList *found)
+{
+ JsonPathExecResult jper;
+ JsonPathExecResult jper2;
+ JsonPathItem elem;
+ JsonValueList seq = {0};
+ JsonValueListIterator it;
+ JsonbValue *val;
+ bool hasNext;
+
+ jspGetArg(jsp, &elem);
+ jper = executeItemOptUnwrapResult(cxt, &elem, jb, true, &seq);
+
+ if (jperIsError(jper))
+ return jper;
+
+ jper = jperNotFound;
+
+ hasNext = jspGetNext(jsp, &elem);
+
+ JsonValueListInitIterator(&seq, &it);
+ while ((val = JsonValueListNext(&seq, &it)))
+ {
+ if ((val = getScalar(val, jbvNumeric)))
+ {
+ if (!found && !hasNext)
+ return jperOk;
+ }
+ else
+ {
+ if (!found && !hasNext)
+ continue; /* skip non-numerics processing */
+
+ RETURN_ERROR(ereport(ERROR,
+ (errcode(ERRCODE_JSON_NUMBER_NOT_FOUND),
+ errmsg(ERRMSG_JSON_NUMBER_NOT_FOUND),
+ errdetail("operand of unary jsonpath operator %s "
+ "is not a numeric value",
+ jspOperationName(jsp->type)))));
+ }
+
+ if (func)
+ val->val.numeric =
+ DatumGetNumeric(DirectFunctionCall1(func,
+ NumericGetDatum(val->val.numeric)));
+
+ jper2 = executeNextItem(cxt, jsp, &elem, val, found, false);
+
+ if (jperIsError(jper2))
+ return jper2;
+
+ if (jper2 == jperOk)
+ {
+ if (!found)
+ return jperOk;
+ jper = jperOk;
+ }
+ }
+
+ return jper;
+}
+
+/*
+ * STARTS_WITH predicate callback.
+ *
+ * Check if the 'whole' string starts from 'initial' string.
+ */
+static JsonPathBool
+executeStartsWith(JsonPathItem *jsp, JsonbValue *whole, JsonbValue *initial,
+ void *param)
+{
+ if (!(whole = getScalar(whole, jbvString)))
+ return jpbUnknown; /* error */
+
+ if (!(initial = getScalar(initial, jbvString)))
+ return jpbUnknown; /* error */
+
+ if (whole->val.string.len >= initial->val.string.len &&
+ !memcmp(whole->val.string.val,
+ initial->val.string.val,
+ initial->val.string.len))
+ return jpbTrue;
+
+ return jpbFalse;
+}
+
+/*
+ * LIKE_REGEX predicate callback.
+ *
+ * Check if the string matches regex pattern.
+ */
+static JsonPathBool
+executeLikeRegex(JsonPathItem *jsp, JsonbValue *str, JsonbValue *rarg,
+ void *param)
+{
+ JsonLikeRegexContext *cxt = param;
+
+ if (!(str = getScalar(str, jbvString)))
+ return jpbUnknown;
+
+ /* Cache regex text and converted flags. */
+ if (!cxt->regex)
+ {
+ uint32 flags = jsp->content.like_regex.flags;
+
+ cxt->regex =
+ cstring_to_text_with_len(jsp->content.like_regex.pattern,
+ jsp->content.like_regex.patternlen);
+
+ /* Convert regex flags. */
+ cxt->cflags = REG_ADVANCED;
+
+ if (flags & JSP_REGEX_ICASE)
+ cxt->cflags |= REG_ICASE;
+ if (flags & JSP_REGEX_MLINE)
+ cxt->cflags |= REG_NEWLINE;
+ if (flags & JSP_REGEX_SLINE)
+ cxt->cflags &= ~REG_NEWLINE;
+ if (flags & JSP_REGEX_WSPACE)
+ cxt->cflags |= REG_EXPANDED;
+ }
+
+ if (RE_compile_and_execute(cxt->regex, str->val.string.val,
+ str->val.string.len,
+ cxt->cflags, DEFAULT_COLLATION_OID, 0, NULL))
+ return jpbTrue;
+
+ return jpbFalse;
+}
+
+/*
+ * Execute numeric item methods (.abs(), .floor(), .ceil()) using the specified
+ * user function 'func'.
+ */
+static JsonPathExecResult
+executeNumericItemMethod(JsonPathExecContext *cxt, JsonPathItem *jsp,
+ JsonbValue *jb, bool unwrap, PGFunction func,
+ JsonValueList *found)
+{
+ JsonPathItem next;
+ Datum datum;
+
+ if (unwrap && JsonbType(jb) == jbvArray)
+ return executeItemUnwrapTargetArray(cxt, jsp, jb, found, false);
+
+ if (!(jb = getScalar(jb, jbvNumeric)))
+ RETURN_ERROR(ereport(ERROR,
+ (errcode(ERRCODE_NON_NUMERIC_JSON_ITEM),
+ errmsg(ERRMSG_NON_NUMERIC_JSON_ITEM),
+ errdetail("jsonpath item method .%s() can only "
+ "be applied to a numeric value",
+ jspOperationName(jsp->type)))));
+
+ datum = NumericGetDatum(jb->val.numeric);
+ datum = DirectFunctionCall1(func, datum);
+
+ if (!jspGetNext(jsp, &next) && !found)
+ return jperOk;
+
+ jb = palloc(sizeof(*jb));
+ jb->type = jbvNumeric;
+ jb->val.numeric = DatumGetNumeric(datum);
+
+ return executeNextItem(cxt, jsp, &next, jb, found, false);
+}
+
+/*
+ * Implementation of .keyvalue() method.
+ *
+ * .keyvalue() method returns a sequence of object's key-value pairs in the
+ * following format: '{ "key": key, "value": value, "id": id }'.
+ *
+ * "id" field is an object identifier which is constructed from the two parts:
+ * base object id and its binary offset in base object's jsonb:
+ * id = 10000000000 * base_object_id + obj_offset_in_base_object
+ *
+ * 10000000000 (10^10) -- is a first round decimal number greater than 2^32
+ * (maximal offset in jsonb). Decimal multiplier is used here to improve the
+ * readability of identifiers.
+ *
+ * Base object is usually a root object of the path: context item '$' or path
+ * variable '$var', literals can't produce objects for now. But if the path
+ * contains generated objects (.keyvalue() itself, for example), then they
+ * become base object for the subsequent .keyvalue().
+ *
+ * Id of '$' is 0. Id of '$var' is its ordinal (positive) number in the list
+ * of variables (see getJsonPathVariable()). Ids for generated objects
+ * are assigned using global counter JsonPathExecContext.lastGeneratedObjectId.
+ */
+static JsonPathExecResult
+executeKeyValueMethod(JsonPathExecContext *cxt, JsonPathItem *jsp,
+ JsonbValue *jb, JsonValueList *found)
+{
+ JsonPathExecResult res = jperNotFound;
+ JsonPathItem next;
+ JsonbContainer *jbc;
+ JsonbValue key;
+ JsonbValue val;
+ JsonbValue idval;
+ JsonbValue keystr;
+ JsonbValue valstr;
+ JsonbValue idstr;
+ JsonbIterator *it;
+ JsonbIteratorToken tok;
+ int64 id;
+ bool hasNext;
+
+ if (JsonbType(jb) != jbvObject || jb->type != jbvBinary)
+ RETURN_ERROR(ereport(ERROR,
+ (errcode(ERRCODE_JSON_OBJECT_NOT_FOUND),
+ errmsg(ERRMSG_JSON_OBJECT_NOT_FOUND),
+ errdetail("jsonpath item method .%s() "
+ "can only be applied to an object",
+ jspOperationName(jsp->type)))));
+
+ jbc = jb->val.binary.data;
+
+ if (!JsonContainerSize(jbc))
+ return jperNotFound; /* no key-value pairs */
+
+ hasNext = jspGetNext(jsp, &next);
+
+ keystr.type = jbvString;
+ keystr.val.string.val = "key";
+ keystr.val.string.len = 3;
+
+ valstr.type = jbvString;
+ valstr.val.string.val = "value";
+ valstr.val.string.len = 5;
+
+ idstr.type = jbvString;
+ idstr.val.string.val = "id";
+ idstr.val.string.len = 2;
+
+ /* construct object id from its base object and offset inside that */
+ id = jb->type != jbvBinary ? 0 :
+ (int64) ((char *) jbc - (char *) cxt->baseObject.jbc);
+ id += (int64) cxt->baseObject.id * INT64CONST(10000000000);
+
+ idval.type = jbvNumeric;
+ idval.val.numeric = DatumGetNumeric(DirectFunctionCall1(int8_numeric,
+ Int64GetDatum(id)));
+
+ it = JsonbIteratorInit(jbc);
+
+ while ((tok = JsonbIteratorNext(&it, &key, true)) != WJB_DONE)
+ {
+ JsonBaseObjectInfo baseObject;
+ JsonbValue obj;
+ JsonbParseState *ps;
+ JsonbValue *keyval;
+ Jsonb *jsonb;
+
+ if (tok != WJB_KEY)
+ continue;
+
+ res = jperOk;
+
+ if (!hasNext && !found)
+ break;
+
+ tok = JsonbIteratorNext(&it, &val, true);
+ Assert(tok == WJB_VALUE);
+
+ ps = NULL;
+ pushJsonbValue(&ps, WJB_BEGIN_OBJECT, NULL);
+
+ pushJsonbValue(&ps, WJB_KEY, &keystr);
+ pushJsonbValue(&ps, WJB_VALUE, &key);
+
+ pushJsonbValue(&ps, WJB_KEY, &valstr);
+ pushJsonbValue(&ps, WJB_VALUE, &val);
+
+ pushJsonbValue(&ps, WJB_KEY, &idstr);
+ pushJsonbValue(&ps, WJB_VALUE, &idval);
+
+ keyval = pushJsonbValue(&ps, WJB_END_OBJECT, NULL);
+
+ jsonb = JsonbValueToJsonb(keyval);
+
+ JsonbInitBinary(&obj, jsonb);
+
+ baseObject = setBaseObject(cxt, &obj, cxt->lastGeneratedObjectId++);
+
+ res = executeNextItem(cxt, jsp, &next, &obj, found, true);
+
+ cxt->baseObject = baseObject;
+
+ if (jperIsError(res))
+ return res;
+
+ if (res == jperOk && !found)
+ break;
+ }
+
+ return res;
+}
+
+/*
+ * Convert boolean execution status 'res' to a boolean JSON item and execute
+ * next jsonpath.
+ */
+static JsonPathExecResult
+appendBoolResult(JsonPathExecContext *cxt, JsonPathItem *jsp,
+ JsonValueList *found, JsonPathBool res)
+{
+ JsonPathItem next;
+ JsonbValue jbv;
+
+ if (!jspGetNext(jsp, &next) && !found)
+ return jperOk; /* found singleton boolean value */
+
+ if (res == jpbUnknown)
+ {
+ jbv.type = jbvNull;
+ }
+ else
+ {
+ jbv.type = jbvBool;
+ jbv.val.boolean = res == jpbTrue;
+ }
+
+ return executeNextItem(cxt, jsp, &next, &jbv, found, true);
+}
+
+/*
+ * Convert jsonpath's scalar or variable node to actual jsonb value.
+ *
+ * If node is a variable then its id returned, otherwise 0 returned.
+ */
+static void
+getJsonPathItem(JsonPathExecContext *cxt, JsonPathItem *item,
+ JsonbValue *value)
+{
+ switch (item->type)
+ {
+ case jpiNull:
+ value->type = jbvNull;
+ break;
+ case jpiBool:
+ value->type = jbvBool;
+ value->val.boolean = jspGetBool(item);
+ break;
+ case jpiNumeric:
+ value->type = jbvNumeric;
+ value->val.numeric = jspGetNumeric(item);
+ break;
+ case jpiString:
+ value->type = jbvString;
+ value->val.string.val = jspGetString(item,
+ &value->val.string.len);
+ break;
+ case jpiVariable:
+ getJsonPathVariable(cxt, item, cxt->vars, value);
+ return;
+ default:
+ elog(ERROR, "unexpected jsonpath item type");
+ }
+}
+
+/*
+ * Get the value of variable passed to jsonpath executor
+ */
+static void
+getJsonPathVariable(JsonPathExecContext *cxt, JsonPathItem *variable,
+ Jsonb *vars, JsonbValue *value)
+{
+ char *varName;
+ int varNameLength;
+ JsonbValue tmp;
+ JsonbValue *v;
+
+ if (!vars)
+ {
+ value->type = jbvNull;
+ return;
+ }
+
+ Assert(variable->type == jpiVariable);
+ varName = jspGetString(variable, &varNameLength);
+ tmp.type = jbvString;
+ tmp.val.string.val = varName;
+ tmp.val.string.len = varNameLength;
+
+ v = findJsonbValueFromContainer(&vars->root, JB_FOBJECT, &tmp);
+
+ if (v)
+ {
+ *value = *v;
+ pfree(v);
+ }
+ else
+ {
+ ereport(ERROR,
+ (errcode(ERRCODE_UNDEFINED_OBJECT),
+ errmsg("cannot find jsonpath variable '%s'",
+ pnstrdup(varName, varNameLength))));
+ }
+
+ JsonbInitBinary(&tmp, vars);
+ setBaseObject(cxt, &tmp, 1);
+}
+
+/**************** Support functions for JsonPath execution *****************/
+
+/*
+ * Returns the size of an array item, or -1 if item is not an array.
+ */
+static int
+JsonbArraySize(JsonbValue *jb)
+{
+ Assert(jb->type != jbvArray);
+
+ if (jb->type == jbvBinary)
+ {
+ JsonbContainer *jbc = jb->val.binary.data;
+
+ if (JsonContainerIsArray(jbc) && !JsonContainerIsScalar(jbc))
+ return JsonContainerSize(jbc);
+ }
+
+ return -1;
+}
+
+/* Comparison predicate callback. */
+static JsonPathBool
+executeComparison(JsonPathItem *cmp, JsonbValue *lv, JsonbValue *rv, void *p)
+{
+ return compareItems(cmp->type, lv, rv);
+}
+
+/*
+ * Compare two SQL/JSON items using comparison operation 'op'.
+ */
+static JsonPathBool
+compareItems(int32 op, JsonbValue *jb1, JsonbValue *jb2)
+{
+ int cmp;
+ bool res;
+
+ if (jb1->type != jb2->type)
+ {
+ if (jb1->type == jbvNull || jb2->type == jbvNull)
+
+ /*
+ * Equality and order comparison of nulls to non-nulls returns
+ * always false, but inequality comparison returns true.
+ */
+ return op == jpiNotEqual ? jpbTrue : jpbFalse;
+
+ /* Non-null items of different types are not comparable. */
+ return jpbUnknown;
+ }
+
+ switch (jb1->type)
+ {
+ case jbvNull:
+ cmp = 0;
+ break;
+ case jbvBool:
+ cmp = jb1->val.boolean == jb2->val.boolean ? 0 :
+ jb1->val.boolean ? 1 : -1;
+ break;
+ case jbvNumeric:
+ cmp = compareNumeric(jb1->val.numeric, jb2->val.numeric);
+ break;
+ case jbvString:
+ if (op == jpiEqual)
+ return jb1->val.string.len != jb2->val.string.len ||
+ memcmp(jb1->val.string.val,
+ jb2->val.string.val,
+ jb1->val.string.len) ? jpbFalse : jpbTrue;
+
+ cmp = varstr_cmp(jb1->val.string.val, jb1->val.string.len,
+ jb2->val.string.val, jb2->val.string.len,
+ DEFAULT_COLLATION_OID);
+ break;
+
+ case jbvBinary:
+ case jbvArray:
+ case jbvObject:
+ return jpbUnknown; /* non-scalars are not comparable */
+
+ default:
+ elog(ERROR, "invalid jsonb value type %d", jb1->type);
+ }
+
+ switch (op)
+ {
+ case jpiEqual:
+ res = (cmp == 0);
+ break;
+ case jpiNotEqual:
+ res = (cmp != 0);
+ break;
+ case jpiLess:
+ res = (cmp < 0);
+ break;
+ case jpiGreater:
+ res = (cmp > 0);
+ break;
+ case jpiLessOrEqual:
+ res = (cmp <= 0);
+ break;
+ case jpiGreaterOrEqual:
+ res = (cmp >= 0);
+ break;
+ default:
+ elog(ERROR, "unrecognized jsonpath operation: %d", op);
+ return jpbUnknown;
+ }
+
+ return res ? jpbTrue : jpbFalse;
+}
+
+/* Compare two numerics */
+static int
+compareNumeric(Numeric a, Numeric b)
+{
+ return DatumGetInt32(DirectFunctionCall2(numeric_cmp,
+ PointerGetDatum(a),
+ PointerGetDatum(b)));
+}
+
+static JsonbValue *
+copyJsonbValue(JsonbValue *src)
+{
+ JsonbValue *dst = palloc(sizeof(*dst));
+
+ *dst = *src;
+
+ return dst;
+}
+
+/*
+ * Execute array subscript expression and convert resulting numeric item to
+ * the integer type with truncation.
+ */
+static JsonPathExecResult
+getArrayIndex(JsonPathExecContext *cxt, JsonPathItem *jsp, JsonbValue *jb,
+ int32 *index)
+{
+ JsonbValue *jbv;
+ JsonValueList found = {0};
+ JsonPathExecResult res = executeItem(cxt, jsp, jb, &found);
+ Datum numeric_index;
+
+ if (jperIsError(res))
+ return res;
+
+ if (JsonValueListLength(&found) != 1 ||
+ !(jbv = getScalar(JsonValueListHead(&found), jbvNumeric)))
+ RETURN_ERROR(ereport(ERROR,
+ (errcode(ERRCODE_INVALID_JSON_SUBSCRIPT),
+ errmsg(ERRMSG_INVALID_JSON_SUBSCRIPT),
+ errdetail("jsonpath array subscript is not a "
+ "singleton numeric value"))));
+
+ numeric_index = DirectFunctionCall2(numeric_trunc,
+ NumericGetDatum(jbv->val.numeric),
+ Int32GetDatum(0));
+
+ *index = DatumGetInt32(DirectFunctionCall1(numeric_int4, numeric_index));
+
+ return jperOk;
+}
+
+/* Save base object and its id needed for the execution of .keyvalue(). */
+static JsonBaseObjectInfo
+setBaseObject(JsonPathExecContext *cxt, JsonbValue *jbv, int32 id)
+{
+ JsonBaseObjectInfo baseObject = cxt->baseObject;
+
+ cxt->baseObject.jbc = jbv->type != jbvBinary ? NULL :
+ (JsonbContainer *) jbv->val.binary.data;
+ cxt->baseObject.id = id;
+
+ return baseObject;
+}
+
+static void
+JsonValueListAppend(JsonValueList *jvl, JsonbValue *jbv)
+{
+ if (jvl->singleton)
+ {
+ jvl->list = list_make2(jvl->singleton, jbv);
+ jvl->singleton = NULL;
+ }
+ else if (!jvl->list)
+ jvl->singleton = jbv;
+ else
+ jvl->list = lappend(jvl->list, jbv);
+}
+
+static int
+JsonValueListLength(const JsonValueList *jvl)
+{
+ return jvl->singleton ? 1 : list_length(jvl->list);
+}
+
+static bool
+JsonValueListIsEmpty(JsonValueList *jvl)
+{
+ return !jvl->singleton && list_length(jvl->list) <= 0;
+}
+
+static JsonbValue *
+JsonValueListHead(JsonValueList *jvl)
+{
+ return jvl->singleton ? jvl->singleton : linitial(jvl->list);
+}
+
+static List *
+JsonValueListGetList(JsonValueList *jvl)
+{
+ if (jvl->singleton)
+ return list_make1(jvl->singleton);
+
+ return jvl->list;
+}
+
+static void
+JsonValueListInitIterator(const JsonValueList *jvl, JsonValueListIterator *it)
+{
+ if (jvl->singleton)
+ {
+ it->value = jvl->singleton;
+ it->next = NULL;
+ }
+ else if (list_head(jvl->list) != NULL)
+ {
+ it->value = (JsonbValue *) linitial(jvl->list);
+ it->next = lnext(list_head(jvl->list));
+ }
+ else
+ {
+ it->value = NULL;
+ it->next = NULL;
+ }
+}
+
+/*
+ * Get the next item from the sequence advancing iterator.
+ */
+static JsonbValue *
+JsonValueListNext(const JsonValueList *jvl, JsonValueListIterator *it)
+{
+ JsonbValue *result = it->value;
+
+ if (it->next)
+ {
+ it->value = lfirst(it->next);
+ it->next = lnext(it->next);
+ }
+ else
+ {
+ it->value = NULL;
+ }
+
+ return result;
+}
+
+/*
+ * Initialize a binary JsonbValue with the given jsonb container.
+ */
+static JsonbValue *
+JsonbInitBinary(JsonbValue *jbv, Jsonb *jb)
+{
+ jbv->type = jbvBinary;
+ jbv->val.binary.data = &jb->root;
+ jbv->val.binary.len = VARSIZE_ANY_EXHDR(jb);
+
+ return jbv;
+}
+
+/*
+ * Returns jbv* type of of JsonbValue. Note, it never returns jbvBinary as is.
+ */
+static int
+JsonbType(JsonbValue *jb)
+{
+ int type = jb->type;
+
+ if (jb->type == jbvBinary)
+ {
+ JsonbContainer *jbc = (void *) jb->val.binary.data;
+
+ /* Scalars should be always extracted during jsonpath execution. */
+ Assert(!JsonContainerIsScalar(jbc));
+
+ if (JsonContainerIsObject(jbc))
+ type = jbvObject;
+ else if (JsonContainerIsArray(jbc))
+ type = jbvArray;
+ else
+ elog(ERROR, "invalid jsonb container type: 0x%08x", jbc->header);
+ }
+
+ return type;
+}
+
+/* Get scalar of given type or NULL on type mismatch */
+static JsonbValue *
+getScalar(JsonbValue *scalar, enum jbvType type)
+{
+ /* Scalars should be always extracted during jsonpath execution. */
+ Assert(scalar->type != jbvBinary ||
+ !JsonContainerIsScalar(scalar->val.binary.data));
+
+ return scalar->type == type ? scalar : NULL;
+}
+
+/* Construct a JSON array from the item list */
+static JsonbValue *
+wrapItemsInArray(const JsonValueList *items)
+{
+ JsonbParseState *ps = NULL;
+ JsonValueListIterator it;
+ JsonbValue *jbv;
+
+ pushJsonbValue(&ps, WJB_BEGIN_ARRAY, NULL);
+
+ JsonValueListInitIterator(items, &it);
+ while ((jbv = JsonValueListNext(items, &it)))
+ pushJsonbValue(&ps, WJB_ELEM, jbv);
+
+ return pushJsonbValue(&ps, WJB_END_ARRAY, NULL);
+}
--- /dev/null
+/*-------------------------------------------------------------------------
+ *
+ * jsonpath_gram.y
+ * Grammar definitions for jsonpath datatype
+ *
+ * Copyright (c) 2019, PostgreSQL Global Development Group
+ *
+ * IDENTIFICATION
+ * src/backend/utils/adt/jsonpath_gram.y
+ *
+ *-------------------------------------------------------------------------
+ */
+
+%{
+#include "postgres.h"
+
+#include "catalog/pg_collation.h"
+#include "fmgr.h"
+#include "miscadmin.h"
+#include "nodes/pg_list.h"
+#include "regex/regex.h"
+#include "utils/builtins.h"
+#include "utils/jsonpath.h"
+#include "utils/jsonpath_scanner.h"
+
+/*
+ * Bison doesn't allocate anything that needs to live across parser calls,
+ * so we can easily have it use palloc instead of malloc. This prevents
+ * memory leaks if we error out during parsing. Note this only works with
+ * bison >= 2.0. However, in bison 1.875 the default is to use alloca()
+ * if possible, so there's not really much problem anyhow, at least if
+ * you're building with gcc.
+ */
+#define YYMALLOC palloc
+#define YYFREE pfree
+
+static JsonPathParseItem*
+makeItemType(int type)
+{
+ JsonPathParseItem* v = palloc(sizeof(*v));
+
+ CHECK_FOR_INTERRUPTS();
+
+ v->type = type;
+ v->next = NULL;
+
+ return v;
+}
+
+static JsonPathParseItem*
+makeItemString(string *s)
+{
+ JsonPathParseItem *v;
+
+ if (s == NULL)
+ {
+ v = makeItemType(jpiNull);
+ }
+ else
+ {
+ v = makeItemType(jpiString);
+ v->value.string.val = s->val;
+ v->value.string.len = s->len;
+ }
+
+ return v;
+}
+
+static JsonPathParseItem*
+makeItemVariable(string *s)
+{
+ JsonPathParseItem *v;
+
+ v = makeItemType(jpiVariable);
+ v->value.string.val = s->val;
+ v->value.string.len = s->len;
+
+ return v;
+}
+
+static JsonPathParseItem*
+makeItemKey(string *s)
+{
+ JsonPathParseItem *v;
+
+ v = makeItemString(s);
+ v->type = jpiKey;
+
+ return v;
+}
+
+static JsonPathParseItem*
+makeItemNumeric(string *s)
+{
+ JsonPathParseItem *v;
+
+ v = makeItemType(jpiNumeric);
+ v->value.numeric =
+ DatumGetNumeric(DirectFunctionCall3(numeric_in,
+ CStringGetDatum(s->val), 0, -1));
+
+ return v;
+}
+
+static JsonPathParseItem*
+makeItemBool(bool val) {
+ JsonPathParseItem *v = makeItemType(jpiBool);
+
+ v->value.boolean = val;
+
+ return v;
+}
+
+static JsonPathParseItem*
+makeItemBinary(int type, JsonPathParseItem* la, JsonPathParseItem *ra)
+{
+ JsonPathParseItem *v = makeItemType(type);
+
+ v->value.args.left = la;
+ v->value.args.right = ra;
+
+ return v;
+}
+
+static JsonPathParseItem*
+makeItemUnary(int type, JsonPathParseItem* a)
+{
+ JsonPathParseItem *v;
+
+ if (type == jpiPlus && a->type == jpiNumeric && !a->next)
+ return a;
+
+ if (type == jpiMinus && a->type == jpiNumeric && !a->next)
+ {
+ v = makeItemType(jpiNumeric);
+ v->value.numeric =
+ DatumGetNumeric(DirectFunctionCall1(numeric_uminus,
+ NumericGetDatum(a->value.numeric)));
+ return v;
+ }
+
+ v = makeItemType(type);
+
+ v->value.arg = a;
+
+ return v;
+}
+
+static JsonPathParseItem*
+makeItemList(List *list)
+{
+ JsonPathParseItem *head, *end;
+ ListCell *cell = list_head(list);
+
+ head = end = (JsonPathParseItem *) lfirst(cell);
+
+ if (!lnext(cell))
+ return head;
+
+ /* append items to the end of already existing list */
+ while (end->next)
+ end = end->next;
+
+ for_each_cell(cell, lnext(cell))
+ {
+ JsonPathParseItem *c = (JsonPathParseItem *) lfirst(cell);
+
+ end->next = c;
+ end = c;
+ }
+
+ return head;
+}
+
+static JsonPathParseItem*
+makeIndexArray(List *list)
+{
+ JsonPathParseItem *v = makeItemType(jpiIndexArray);
+ ListCell *cell;
+ int i = 0;
+
+ Assert(list_length(list) > 0);
+ v->value.array.nelems = list_length(list);
+
+ v->value.array.elems = palloc(sizeof(v->value.array.elems[0]) *
+ v->value.array.nelems);
+
+ foreach(cell, list)
+ {
+ JsonPathParseItem *jpi = lfirst(cell);
+
+ Assert(jpi->type == jpiSubscript);
+
+ v->value.array.elems[i].from = jpi->value.args.left;
+ v->value.array.elems[i++].to = jpi->value.args.right;
+ }
+
+ return v;
+}
+
+static JsonPathParseItem*
+makeAny(int first, int last)
+{
+ JsonPathParseItem *v = makeItemType(jpiAny);
+
+ v->value.anybounds.first = (first >= 0) ? first : PG_UINT32_MAX;
+ v->value.anybounds.last = (last >= 0) ? last : PG_UINT32_MAX;
+
+ return v;
+}
+
+static JsonPathParseItem *
+makeItemLikeRegex(JsonPathParseItem *expr, string *pattern, string *flags)
+{
+ JsonPathParseItem *v = makeItemType(jpiLikeRegex);
+ int i;
+ int cflags = REG_ADVANCED;
+
+ v->value.like_regex.expr = expr;
+ v->value.like_regex.pattern = pattern->val;
+ v->value.like_regex.patternlen = pattern->len;
+ v->value.like_regex.flags = 0;
+
+ for (i = 0; flags && i < flags->len; i++)
+ {
+ switch (flags->val[i])
+ {
+ case 'i':
+ v->value.like_regex.flags |= JSP_REGEX_ICASE;
+ cflags |= REG_ICASE;
+ break;
+ case 's':
+ v->value.like_regex.flags &= ~JSP_REGEX_MLINE;
+ v->value.like_regex.flags |= JSP_REGEX_SLINE;
+ cflags |= REG_NEWLINE;
+ break;
+ case 'm':
+ v->value.like_regex.flags &= ~JSP_REGEX_SLINE;
+ v->value.like_regex.flags |= JSP_REGEX_MLINE;
+ cflags &= ~REG_NEWLINE;
+ break;
+ case 'x':
+ v->value.like_regex.flags |= JSP_REGEX_WSPACE;
+ cflags |= REG_EXPANDED;
+ break;
+ default:
+ yyerror(NULL, "unrecognized flag of LIKE_REGEX predicate");
+ break;
+ }
+ }
+
+ /* check regex validity */
+ (void) RE_compile_and_cache(cstring_to_text_with_len(pattern->val,
+ pattern->len),
+ cflags, DEFAULT_COLLATION_OID);
+
+ return v;
+}
+
+%}
+
+/* BISON Declarations */
+%pure-parser
+%expect 0
+%name-prefix="jsonpath_yy"
+%error-verbose
+%parse-param {JsonPathParseResult **result}
+
+%union {
+ string str;
+ List *elems; /* list of JsonPathParseItem */
+ List *indexs; /* list of integers */
+ JsonPathParseItem *value;
+ JsonPathParseResult *result;
+ JsonPathItemType optype;
+ bool boolean;
+ int integer;
+}
+
+%token <str> TO_P NULL_P TRUE_P FALSE_P IS_P UNKNOWN_P EXISTS_P
+%token <str> IDENT_P STRING_P NUMERIC_P INT_P VARIABLE_P
+%token <str> OR_P AND_P NOT_P
+%token <str> LESS_P LESSEQUAL_P EQUAL_P NOTEQUAL_P GREATEREQUAL_P GREATER_P
+%token <str> ANY_P STRICT_P LAX_P LAST_P STARTS_P WITH_P LIKE_REGEX_P FLAG_P
+%token <str> ABS_P SIZE_P TYPE_P FLOOR_P DOUBLE_P CEILING_P KEYVALUE_P
+
+%type <result> result
+
+%type <value> scalar_value path_primary expr array_accessor
+ any_path accessor_op key predicate delimited_predicate
+ index_elem starts_with_initial expr_or_predicate
+
+%type <elems> accessor_expr
+
+%type <indexs> index_list
+
+%type <optype> comp_op method
+
+%type <boolean> mode
+
+%type <str> key_name
+
+%type <integer> any_level
+
+%left OR_P
+%left AND_P
+%right NOT_P
+%left '+' '-'
+%left '*' '/' '%'
+%left UMINUS
+%nonassoc '(' ')'
+
+/* Grammar follows */
+%%
+
+result:
+ mode expr_or_predicate {
+ *result = palloc(sizeof(JsonPathParseResult));
+ (*result)->expr = $2;
+ (*result)->lax = $1;
+ }
+ | /* EMPTY */ { *result = NULL; }
+ ;
+
+expr_or_predicate:
+ expr { $$ = $1; }
+ | predicate { $$ = $1; }
+ ;
+
+mode:
+ STRICT_P { $$ = false; }
+ | LAX_P { $$ = true; }
+ | /* EMPTY */ { $$ = true; }
+ ;
+
+scalar_value:
+ STRING_P { $$ = makeItemString(&$1); }
+ | NULL_P { $$ = makeItemString(NULL); }
+ | TRUE_P { $$ = makeItemBool(true); }
+ | FALSE_P { $$ = makeItemBool(false); }
+ | NUMERIC_P { $$ = makeItemNumeric(&$1); }
+ | INT_P { $$ = makeItemNumeric(&$1); }
+ | VARIABLE_P { $$ = makeItemVariable(&$1); }
+ ;
+
+comp_op:
+ EQUAL_P { $$ = jpiEqual; }
+ | NOTEQUAL_P { $$ = jpiNotEqual; }
+ | LESS_P { $$ = jpiLess; }
+ | GREATER_P { $$ = jpiGreater; }
+ | LESSEQUAL_P { $$ = jpiLessOrEqual; }
+ | GREATEREQUAL_P { $$ = jpiGreaterOrEqual; }
+ ;
+
+delimited_predicate:
+ '(' predicate ')' { $$ = $2; }
+ | EXISTS_P '(' expr ')' { $$ = makeItemUnary(jpiExists, $3); }
+ ;
+
+predicate:
+ delimited_predicate { $$ = $1; }
+ | expr comp_op expr { $$ = makeItemBinary($2, $1, $3); }
+ | predicate AND_P predicate { $$ = makeItemBinary(jpiAnd, $1, $3); }
+ | predicate OR_P predicate { $$ = makeItemBinary(jpiOr, $1, $3); }
+ | NOT_P delimited_predicate { $$ = makeItemUnary(jpiNot, $2); }
+ | '(' predicate ')' IS_P UNKNOWN_P { $$ = makeItemUnary(jpiIsUnknown, $2); }
+ | expr STARTS_P WITH_P starts_with_initial
+ { $$ = makeItemBinary(jpiStartsWith, $1, $4); }
+ | expr LIKE_REGEX_P STRING_P { $$ = makeItemLikeRegex($1, &$3, NULL); }
+ | expr LIKE_REGEX_P STRING_P FLAG_P STRING_P
+ { $$ = makeItemLikeRegex($1, &$3, &$5); }
+ ;
+
+starts_with_initial:
+ STRING_P { $$ = makeItemString(&$1); }
+ | VARIABLE_P { $$ = makeItemVariable(&$1); }
+ ;
+
+path_primary:
+ scalar_value { $$ = $1; }
+ | '$' { $$ = makeItemType(jpiRoot); }
+ | '@' { $$ = makeItemType(jpiCurrent); }
+ | LAST_P { $$ = makeItemType(jpiLast); }
+ ;
+
+accessor_expr:
+ path_primary { $$ = list_make1($1); }
+ | '(' expr ')' accessor_op { $$ = list_make2($2, $4); }
+ | '(' predicate ')' accessor_op { $$ = list_make2($2, $4); }
+ | accessor_expr accessor_op { $$ = lappend($1, $2); }
+ ;
+
+expr:
+ accessor_expr { $$ = makeItemList($1); }
+ | '(' expr ')' { $$ = $2; }
+ | '+' expr %prec UMINUS { $$ = makeItemUnary(jpiPlus, $2); }
+ | '-' expr %prec UMINUS { $$ = makeItemUnary(jpiMinus, $2); }
+ | expr '+' expr { $$ = makeItemBinary(jpiAdd, $1, $3); }
+ | expr '-' expr { $$ = makeItemBinary(jpiSub, $1, $3); }
+ | expr '*' expr { $$ = makeItemBinary(jpiMul, $1, $3); }
+ | expr '/' expr { $$ = makeItemBinary(jpiDiv, $1, $3); }
+ | expr '%' expr { $$ = makeItemBinary(jpiMod, $1, $3); }
+ ;
+
+index_elem:
+ expr { $$ = makeItemBinary(jpiSubscript, $1, NULL); }
+ | expr TO_P expr { $$ = makeItemBinary(jpiSubscript, $1, $3); }
+ ;
+
+index_list:
+ index_elem { $$ = list_make1($1); }
+ | index_list ',' index_elem { $$ = lappend($1, $3); }
+ ;
+
+array_accessor:
+ '[' '*' ']' { $$ = makeItemType(jpiAnyArray); }
+ | '[' index_list ']' { $$ = makeIndexArray($2); }
+ ;
+
+any_level:
+ INT_P { $$ = pg_atoi($1.val, 4, 0); }
+ | LAST_P { $$ = -1; }
+ ;
+
+any_path:
+ ANY_P &
projects / users / bernd / postgres.git / commitdiff