ISO SQL behavior. Backpatch removal to 8.2.X.
expression must be of Boolean type.
</para>
+<!-- IS OF does not conform to the ISO SQL behavior, so it is undocumented here
<para>
<indexterm>
<primary>IS OF</primary>
</synopsis>
They return a boolean value based on whether the expression's data
type is one of the listed data types.
+ </para>
+-->
+
</sect1>
<sect1 id="functions-math">
<row>
<entry><token>IS</token></entry>
<entry></entry>
- <entry><literal>IS TRUE</>, <literal>IS FALSE</>, <literal>IS
- UNKNOWN</>, <literal>IS NULL</>, <literal>IS OF</></entry>
+ <entry><literal>IS TRUE</>, <literal>IS FALSE</>, <literal>IS UNKNOWN</>, <literal>IS NULL</></entry>
</row>
<row>