Movatterモバイル変換

[0]ホーム
URL:

Skip to content

Navigation Menu

Sign in
Appearance settings

Search code, repositories, users, issues, pull requests...

Provide feedback

We read every piece of feedback, and take your input very seriously.

Saved searches

Use saved searches to filter your results more quickly

 Sign up
Appearance settings

Commit4deb57d

Browse files
committed
Issue ERROR if FREEZE mode can't be honored by COPY
Previously non-honored FREEZE mode was ignored. This also issues anappropriate error message based on the cause of the failure, persuggestion from Tom. Additional regression test case added.
1 parent7e2322d commit4deb57d

File tree

4 files changed

+40
-31
lines changed

4 files changed

+40
-31
lines changed

‎doc/src/sgml/ref/copy.sgml

Lines changed: 4 additions & 8 deletions
Original file line numberDiff line numberDiff line change
@@ -190,18 +190,14 @@ COPY { <replaceable class="parameter">table_name</replaceable> [ ( <replaceable
190190
would be after running the <command>VACUUM FREEZE</> command.
191191
This is intended as a performance option for initial data loading.
192192
Rows will be frozen only if the table being loaded has been created
193-
in the current subtransaction, there are no cursors open and there
194-
are no older snapshots held by this transaction. If those conditions
195-
are not met the command will continue without error though will not
196-
freeze rows. It is also possible in rare cases that the request
197-
cannot be honoured for internal reasons, hence <literal>FREEZE</literal>
198-
is more of a guideline than a hard rule.
193+
or truncated in the current subtransaction, there are no cursors
194+
open and there are no older snapshots held by this transaction.
199195
</para>
200196
<para>
201197
Note that all other sessions will immediately be able to see the data
202198
once it has been successfully loaded. This violates the normal rules
203-
of MVCC visibility andby specifyingthis option the user acknowledges
204-
explicitly that thisis understood.
199+
of MVCC visibility andusers specifyingshould be aware of the
200+
potential problems thismight cause.
205201
</para>
206202
</listitem>
207203
</varlistentry>

‎src/backend/commands/copy.c

Lines changed: 20 additions & 12 deletions
Original file line numberDiff line numberDiff line change
@@ -1978,8 +1978,6 @@ CopyFrom(CopyState cstate)
19781978
* ROLLBACK TO save;
19791979
* COPY ...
19801980
*
1981-
* However this is OK since at worst we will fail to make the optimization.
1982-
*
19831981
* Also, if the target file is new-in-transaction, we assume that checking
19841982
* FSM for free space is a waste of time, even if we must use WAL because
19851983
* of archiving. This could possibly be wrong, but it's unlikely.
@@ -1991,6 +1989,7 @@ CopyFrom(CopyState cstate)
19911989
* no additional work to enforce that.
19921990
*----------
19931991
*/
1992+
/* createSubid is creation check, newRelfilenodeSubid is truncation check */
19941993
if (cstate->rel->rd_createSubid!=InvalidSubTransactionId||
19951994
cstate->rel->rd_newRelfilenodeSubid!=InvalidSubTransactionId)
19961995
{
@@ -2006,18 +2005,27 @@ CopyFrom(CopyState cstate)
20062005
* after xact cleanup. Note that the stronger test of exactly
20072006
* which subtransaction created it is crucial for correctness
20082007
* of this optimisation.
2009-
*
2010-
* As noted above rd_newRelfilenodeSubid is not set in all cases
2011-
* where we can apply the optimization, so in those rare cases
2012-
* where we cannot honour the request we do so silently.
20132008
*/
2014-
if (cstate->freeze&&
2015-
ThereAreNoPriorRegisteredSnapshots()&&
2016-
ThereAreNoReadyPortals()&&
2017-
(cstate->rel->rd_newRelfilenodeSubid==GetCurrentSubTransactionId()||
2018-
cstate->rel->rd_createSubid==GetCurrentSubTransactionId()))
2019-
hi_options |=HEAP_INSERT_FROZEN;
2009+
if (cstate->freeze)
2010+
{
2011+
if (!ThereAreNoPriorRegisteredSnapshots()|| !ThereAreNoReadyPortals())
2012+
ereport(ERROR,
2013+
(ERRCODE_INVALID_TRANSACTION_STATE,
2014+
errmsg("cannot perform FREEZE because of prior transaction activity")));
2015+
2016+
if (cstate->rel->rd_createSubid==GetCurrentSubTransactionId()||
2017+
cstate->rel->rd_newRelfilenodeSubid==GetCurrentSubTransactionId())
2018+
hi_options |=HEAP_INSERT_FROZEN;
2019+
else
2020+
ereport(ERROR,
2021+
(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE,
2022+
errmsg("cannot perform FREEZE because of transaction activity after table creation or truncation")));
2023+
}
20202024
}
2025+
elseif (cstate->freeze)
2026+
ereport(ERROR,
2027+
(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE,
2028+
errmsg("cannot perform FREEZE because the table was not created or truncated in the current transaction")));
20212029

20222030
/*
20232031
* We need a ResultRelInfo so we can use the regular executor's

‎src/test/regress/expected/copy2.out

Lines changed: 8 additions & 10 deletions
Original file line numberDiff line numberDiff line change
@@ -334,22 +334,20 @@ SELECT * FROM vistest;
334334
COMMIT;
335335
TRUNCATE vistest;
336336
COPY vistest FROM stdin CSV FREEZE;
337+
ERROR: cannot perform FREEZE because the table was not created or truncated in the current transaction
338+
BEGIN;
339+
TRUNCATE vistest;
340+
SAVEPOINT s1;
341+
COPY vistest FROM stdin CSV FREEZE;
342+
ERROR: cannot perform FREEZE because of transaction activity after table creation or truncation
343+
COMMIT;
337344
BEGIN;
338345
INSERT INTO vistest VALUES ('z');
339346
SAVEPOINT s1;
340347
TRUNCATE vistest;
341348
ROLLBACK TO SAVEPOINT s1;
342349
COPY vistest FROM stdin CSV FREEZE;
343-
SELECT * FROM vistest;
344-
a
345-
----
346-
p
347-
g
348-
z
349-
d3
350-
e
351-
(5 rows)
352-
350+
ERROR: cannot perform FREEZE because the table was not created or truncated in the current transaction
353351
COMMIT;
354352
CREATE FUNCTION truncate_in_subxact() RETURNS VOID AS
355353
$$

‎src/test/regress/sql/copy2.sql

Lines changed: 8 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -234,6 +234,14 @@ p
234234
g
235235
\.
236236
BEGIN;
237+
TRUNCATE vistest;
238+
SAVEPOINT s1;
239+
COPY vistestFROM stdin CSV FREEZE;
240+
m
241+
k
242+
\.
243+
COMMIT;
244+
BEGIN;
237245
INSERT INTO vistestVALUES ('z');
238246
SAVEPOINT s1;
239247
TRUNCATE vistest;
@@ -242,7 +250,6 @@ COPY vistest FROM stdin CSV FREEZE;
242250
d3
243251
e
244252
\.
245-
SELECT*FROM vistest;
246253
COMMIT;
247254
CREATEFUNCTIONtruncate_in_subxact() RETURNS VOIDAS
248255
$$

0 commit comments

Comments
 (0)
[8]ページ先頭
©2009-2025 Movatter.jp