<para>
If the client has not issued an explicit <command>BEGIN</command>,
- then each Sync ordinarily causes an implicit <command>COMMIT</command>
- if the preceding step(s) succeeded, or an
- implicit <command>ROLLBACK</command> if they failed. However, there
- are a few DDL commands (such as <command>CREATE DATABASE</command>)
- that cannot be executed inside a transaction block. If one of
- these is executed in a pipeline, it will fail unless it is the first
- command in the pipeline. Furthermore, upon success it will force an
- immediate commit to preserve database consistency. Thus a Sync
- immediately following one of these commands has no effect except to
- respond with ReadyForQuery.
+ then an implicit transaction block is started and each Sync ordinarily
+ causes an implicit <command>COMMIT</command> if the preceding step(s)
+ succeeded, or an implicit <command>ROLLBACK</command> if they failed.
+ This implicit transaction block will only be detected by the server
+ when the first command ends without a sync. There are a few DDL
+ commands (such as <command>CREATE DATABASE</command>) that cannot be
+ executed inside a transaction block. If one of these is executed in a
+ pipeline, it will fail unless it is the first command after a Sync.
+ Furthermore, upon success it will force an immediate commit to preserve
+ database consistency. Thus a Sync immediately following one of these
+ commands has no effect except to respond with ReadyForQuery.
</para>
<para>
xact_started = true;
}
+ else if (MyXactFlags & XACT_FLAGS_PIPELINING)
+ {
+ /*
+ * When the first Execute message is completed, following commands
+ * will be done in an implicit transaction block created via
+ * pipelining. The transaction state needs to be updated to an
+ * implicit block if we're not already in a transaction block (like
+ * one started by an explicit BEGIN).
+ */
+ BeginImplicitTransactionBlock();
+ }
/*
* Start statement timeout if necessary. Note that this'll intentionally
case 'S': /* sync */
pq_getmsgend(&input_message);
+
+ /*
+ * If pipelining was used, we may be in an implicit
+ * transaction block. Close it before calling
+ * finish_xact_command.
+ */
+ EndImplicitTransactionBlock();
finish_xact_command();
send_ready_for_query = true;
break;
}
});
+# Try SET LOCAL as first pipeline command. This succeeds and the first
+# command is not executed inside an implicit transaction block, causing
+# a WARNING.
+$node->pgbench(
+ '-t 1 -n -M extended',
+ 0,
+ [],
+ [qr{WARNING: SET LOCAL can only be used in transaction blocks}],
+ 'SET LOCAL outside implicit transaction block of pipeline',
+ {
+ '001_pgbench_pipeline_set_local_1' => q{
+\startpipeline
+SET LOCAL statement_timeout='1h';
+\endpipeline
+}
+ });
+
+# Try SET LOCAL as second pipeline command. This succeeds and the second
+# command does not cause a WARNING to be generated.
+$node->pgbench(
+ '-t 1 -n -M extended',
+ 0,
+ [],
+ [qr{^$}],
+ 'SET LOCAL inside implicit transaction block of pipeline',
+ {
+ '001_pgbench_pipeline_set_local_2' => q{
+\startpipeline
+SELECT 1;
+SET LOCAL statement_timeout='1h';
+\endpipeline
+}
+ });
+
+# Try REINDEX CONCURRENTLY as first pipeline command. This succeeds
+# as the first command is outside the implicit transaction block of
+# a pipeline.
+$node->pgbench(
+ '-t 1 -n -M extended',
+ 0,
+ [],
+ [],
+ 'REINDEX CONCURRENTLY outside implicit transaction block of pipeline',
+ {
+ '001_pgbench_pipeline_reindex_1' => q{
+\startpipeline
+REINDEX TABLE CONCURRENTLY pgbench_accounts;
+SELECT 1;
+\endpipeline
+}
+ });
+
+# Try REINDEX CONCURRENTLY as second pipeline command. This fails
+# as the second command is inside an implicit transaction block.
+$node->pgbench(
+ '-t 1 -n -M extended',
+ 2,
+ [],
+ [],
+ 'error: REINDEX CONCURRENTLY inside implicit transaction block of pipeline',
+ {
+ '001_pgbench_pipeline_reindex_2' => q{
+\startpipeline
+SELECT 1;
+REINDEX TABLE CONCURRENTLY pgbench_accounts;
+\endpipeline
+}
+ });
+
+# Try VACUUM as first pipeline command. Like REINDEX CONCURRENTLY, this
+# succeeds as this is outside the implicit transaction block of a pipeline.
+$node->pgbench(
+ '-t 1 -n -M extended',
+ 0,
+ [],
+ [],
+ 'VACUUM outside implicit transaction block of pipeline',
+ {
+ '001_pgbench_pipeline_vacuum_1' => q{
+\startpipeline
+VACUUM pgbench_accounts;
+\endpipeline
+}
+ });
+
+# Try VACUUM as second pipeline command. This fails, as the second command
+# of a pipeline is inside an implicit transaction block.
+$node->pgbench(
+ '-t 1 -n -M extended',
+ 2,
+ [],
+ [],
+ 'error: VACUUM inside implicit transaction block of pipeline',
+ {
+ '001_pgbench_pipeline_vacuum_2' => q{
+\startpipeline
+SELECT 1;
+VACUUM pgbench_accounts;
+\endpipeline
+}
+ });
+
+# Try subtransactions in a pipeline. These are forbidden in implicit
+# transaction blocks.
+$node->pgbench(
+ '-t 1 -n -M extended',
+ 2,
+ [],
+ [],
+ 'error: subtransactions not allowed in pipeline',
+ {
+ '001_pgbench_pipeline_subtrans' => q{
+\startpipeline
+SAVEPOINT a;
+SELECT 1;
+ROLLBACK TO SAVEPOINT a;
+SELECT 2;
+\endpipeline
+}
+ });
+
+# Try LOCK TABLE as first pipeline command. This fails as LOCK is outside
+# an implicit transaction block.
+$node->pgbench(
+ '-t 1 -n -M extended',
+ 2,
+ [],
+ [],
+ 'error: LOCK TABLE outside implicit transaction block of pipeline',
+ {
+ '001_pgbench_pipeline_lock_1' => q{
+\startpipeline
+LOCK pgbench_accounts;
+SELECT 1;
+\endpipeline
+}
+ });
+
+# Try LOCK TABLE as second pipeline command. This succeeds as LOCK is inside
+# an implicit transaction block.
+$node->pgbench(
+ '-t 1 -n -M extended',
+ 0,
+ [],
+ [],
+ 'LOCK TABLE inside implicit transaction block of pipeline',
+ {
+ '001_pgbench_pipeline_lock_2' => q{
+\startpipeline
+SELECT 1;
+LOCK pgbench_accounts;
+\endpipeline
+}
+ });
+
# Working \startpipeline in prepared query mode with serializable
$node->pgbench(
'-c4 -t 10 -n -M prepared',
projects / postgresql.git / commitdiff