sharpetronics/PostgreSQL
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-05-28 00:03:23 -04:00
Code Issues Projects Releases Wiki Activity

Revert "Handle better implicit transaction state of pipeline mode"

Browse Source 
This reverts commit d77f91214fb7 on all stable branches, due to concerns
regarding the compatility side effects this could create in a minor
release.  The change still exists on HEAD.

Discussion: https://postgr.es/m/CA+TgmoZqRgeFTg4+Yf_CMRRXiHuNz1u6ZC4FvVk+rxw0RmOPnw@mail.gmail.com
Backpatch-through: 13
This commit is contained in:
Michael Paquier 2024-11-28 09:43:21 +09:00
parent c93dffd89b
commit 7668e85a40
4 changed files with 23 additions and 203 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

21
doc/src/sgml/protocol.sgml
View File

@ -1070,17 +1070,16 @@ SELCT 1/0;<!-- this typo is intentional -->
<para> <para>
If the client has not issued an explicit <command>BEGIN</command>, If the client has not issued an explicit <command>BEGIN</command>,
then an implicit transaction block is started and each Sync ordinarily then each Sync ordinarily causes an implicit <command>COMMIT</command>
causes an implicit <command>COMMIT</command> if the preceding step(s) if the preceding step(s) succeeded, or an
succeeded, or an implicit <command>ROLLBACK</command> if they failed. implicit <command>ROLLBACK</command> if they failed. However, there
This implicit transaction block will only be detected by the server are a few DDL commands (such as <command>CREATE DATABASE</command>)
when the first command ends without a sync. There are a few DDL that cannot be executed inside a transaction block. If one of
commands (such as <command>CREATE DATABASE</command>) that cannot be these is executed in a pipeline, it will fail unless it is the first
executed inside a transaction block. If one of these is executed in a command in the pipeline. Furthermore, upon success it will force an
pipeline, it will fail unless it is the first command after a Sync. immediate commit to preserve database consistency. Thus a Sync
Furthermore, upon success it will force an immediate commit to preserve immediately following one of these commands has no effect except to
database consistency. Thus a Sync immediately following one of these respond with ReadyForQuery.
commands has no effect except to respond with ReadyForQuery.
</para> </para>
<para> <para>

13
src/backend/access/transam/xact.c
View File

@ -3603,6 +3603,16 @@ PreventInTransactionBlock(bool isTopLevel, const char *stmtType)
errmsg("%s cannot run inside a subtransaction", errmsg("%s cannot run inside a subtransaction",
stmtType))); stmtType)));
/*
* inside a pipeline that has started an implicit transaction?
*/
if (MyXactFlags & XACT_FLAGS_PIPELINING)
ereport(ERROR,
(errcode(ERRCODE_ACTIVE_SQL_TRANSACTION),
/* translator: %s represents an SQL statement name */
errmsg("%s cannot be executed within a pipeline",
stmtType)));
/* /*
* inside a function call? * inside a function call?
*/ */
@ -3714,6 +3724,9 @@ IsInTransactionBlock(bool isTopLevel)
if (IsSubTransaction()) if (IsSubTransaction())
return true; return true;
if (MyXactFlags & XACT_FLAGS_PIPELINING)
return true;
if (!isTopLevel) if (!isTopLevel)
return true; return true;

18
src/backend/tcop/postgres.c
View File

@ -2775,17 +2775,6 @@ start_xact_command(void)
xact_started = true; 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 * Start statement timeout if necessary. Note that this'll intentionally
@ -4971,13 +4960,6 @@ PostgresMain(const char *dbname, const char *username)
case PqMsg_Sync: case PqMsg_Sync:
pq_getmsgend(&input_message); 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(); finish_xact_command();
valgrind_report_error_query("SYNC message"); valgrind_report_error_query("SYNC message");
send_ready_for_query = true; send_ready_for_query = true;

174
src/bin/pgbench/t/001_pgbench_with_server.pl
View File

@ -968,180 +968,6 @@ $node->pgbench(
} }
}); });
# 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 SET LOCAL with \syncpipeline. This succeeds and the command
# launched after the sync is outside the implicit transaction block
# of the pipeline, causing a WARNING.
$node->pgbench(
'-t 1 -n -M extended',
0,
[],
[qr{WARNING: SET LOCAL can only be used in transaction blocks}],
'SET LOCAL and \syncpipeline',
{
'001_pgbench_pipeline_set_local_3' => q{
\startpipeline
SELECT 1;
\syncpipeline
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 # Working \startpipeline in prepared query mode with serializable
$node->pgbench( $node->pgbench(
'-c4 -t 10 -n -M prepared', '-c4 -t 10 -n -M prepared',