Changed error message for blocks by prepared transactions
Hello,
the small attached patch changes the error message for a blocked
database in case there are prepared transactions. The original message
"accessed by other users" is misleading.
Example:
----- snip -----
postgres=# begin;
BEGIN
postgres=# prepare transaction 'abc';
PREPARE TRANSACTION
postgres=# \c template1
psql (8.4rc1)
Sie sind jetzt verbunden mit der Datenbank »template1«.
template1=# alter database postgres rename to test;
ERROR: database "postgres" is being blocked by prepared transactions
DETAIL: There are 1 prepared transaction(s) using the database.
----- snip -----
Translation still pending, how to add new messages to the .po files?
Kind regards
--
Andreas 'ads' Scherbaum
German PostgreSQL User Group
European PostgreSQL User Group - Board of Directors
Volunteer Regional Contact, Germany - PostgreSQL Project
PGDay.eu 2009 in Paris, Nov. 6/7, http://www.pgday.eu/
Attachments:
different_msg_for_prep_transactions.difftext/x-patch; name=different_msg_for_prep_transactions.diffDownload
Index: src/backend/commands/dbcommands.c
===================================================================
RCS file: /projects/cvsroot/pgsql/src/backend/commands/dbcommands.c,v
retrieving revision 1.225
diff -u -3 -p -r1.225 dbcommands.c
--- src/backend/commands/dbcommands.c 11 Jun 2009 14:48:55 -0000 1.225
+++ src/backend/commands/dbcommands.c 22 Jun 2009 21:50:23 -0000
@@ -501,11 +501,24 @@ createdb(const CreatedbStmt *stmt)
* throw one.
*/
if (CountOtherDBBackends(src_dboid, ¬herbackends, &npreparedxacts))
- ereport(ERROR,
- (errcode(ERRCODE_OBJECT_IN_USE),
- errmsg("source database \"%s\" is being accessed by other users",
- dbtemplate),
- errdetail_busy_db(notherbackends, npreparedxacts)));
+ {
+ if (npreparedxacts > 0)
+ {
+ ereport(ERROR,
+ (errcode(ERRCODE_OBJECT_IN_USE),
+ errmsg("source database \"%s\" is being blocked by prepared transactions",
+ dbtemplate),
+ errdetail_busy_db(notherbackends, npreparedxacts)));
+ }
+ else
+ {
+ ereport(ERROR,
+ (errcode(ERRCODE_OBJECT_IN_USE),
+ errmsg("source database \"%s\" is being accessed by other users",
+ dbtemplate),
+ errdetail_busy_db(notherbackends, npreparedxacts)));
+ }
+ }
/*
* Select an OID for the new database, checking that it doesn't have a
@@ -799,11 +812,24 @@ dropdb(const char *dbname, bool missing_
* As in CREATE DATABASE, check this after other error conditions.
*/
if (CountOtherDBBackends(db_id, ¬herbackends, &npreparedxacts))
- ereport(ERROR,
- (errcode(ERRCODE_OBJECT_IN_USE),
- errmsg("database \"%s\" is being accessed by other users",
- dbname),
- errdetail_busy_db(notherbackends, npreparedxacts)));
+ {
+ if (npreparedxacts > 0)
+ {
+ ereport(ERROR,
+ (errcode(ERRCODE_OBJECT_IN_USE),
+ errmsg("database \"%s\" is being blocked by prepared transactions",
+ dbname),
+ errdetail_busy_db(notherbackends, npreparedxacts)));
+ }
+ else
+ {
+ ereport(ERROR,
+ (errcode(ERRCODE_OBJECT_IN_USE),
+ errmsg("database \"%s\" is being accessed by other users",
+ dbname),
+ errdetail_busy_db(notherbackends, npreparedxacts)));
+ }
+ }
/*
* Remove the database's tuple from pg_database.
@@ -940,11 +966,24 @@ RenameDatabase(const char *oldname, cons
* As in CREATE DATABASE, check this after other error conditions.
*/
if (CountOtherDBBackends(db_id, ¬herbackends, &npreparedxacts))
- ereport(ERROR,
- (errcode(ERRCODE_OBJECT_IN_USE),
- errmsg("database \"%s\" is being accessed by other users",
- oldname),
- errdetail_busy_db(notherbackends, npreparedxacts)));
+ {
+ if (npreparedxacts > 0)
+ {
+ ereport(ERROR,
+ (errcode(ERRCODE_OBJECT_IN_USE),
+ errmsg("database \"%s\" is being blocked by prepared transactions",
+ oldname),
+ errdetail_busy_db(notherbackends, npreparedxacts)));
+ }
+ else
+ {
+ ereport(ERROR,
+ (errcode(ERRCODE_OBJECT_IN_USE),
+ errmsg("database \"%s\" is being accessed by other users",
+ oldname),
+ errdetail_busy_db(notherbackends, npreparedxacts)));
+ }
+ }
/* rename */
newtup = SearchSysCacheCopy(DATABASEOID,
@@ -1077,11 +1116,24 @@ movedb(const char *dbname, const char *t
* As in CREATE DATABASE, check this after other error conditions.
*/
if (CountOtherDBBackends(db_id, ¬herbackends, &npreparedxacts))
- ereport(ERROR,
- (errcode(ERRCODE_OBJECT_IN_USE),
- errmsg("database \"%s\" is being accessed by other users",
- dbname),
- errdetail_busy_db(notherbackends, npreparedxacts)));
+ {
+ if (npreparedxacts > 0)
+ {
+ ereport(ERROR,
+ (errcode(ERRCODE_OBJECT_IN_USE),
+ errmsg("database \"%s\" is being blocked by prepared transactions",
+ dbname),
+ errdetail_busy_db(notherbackends, npreparedxacts)));
+ }
+ else
+ {
+ ereport(ERROR,
+ (errcode(ERRCODE_OBJECT_IN_USE),
+ errmsg("database \"%s\" is being accessed by other users",
+ dbname),
+ errdetail_busy_db(notherbackends, npreparedxacts)));
+ }
+ }
/*
* Get old and new database paths
"Andreas 'ads' Scherbaum" <adsmail@wars-nicht.de> writes:
the small attached patch changes the error message for a blocked
database in case there are prepared transactions.
Isn't this duplicative of the errdetail_busy_db code? And anyway
I do not see a reason not to consider prepared transactions as
"other users".
regards, tom lane
On Mon, 22 Jun 2009 19:24:28 -0400 Tom Lane wrote:
"Andreas 'ads' Scherbaum" <adsmail@wars-nicht.de> writes:
the small attached patch changes the error message for a blocked
database in case there are prepared transactions.Isn't this duplicative of the errdetail_busy_db code? And anyway
I do not see a reason not to consider prepared transactions as
"other users".
Because you know the details.
Most other users check pg_stat_activity just to find out there is no
other user connected. A prepared transaction is not a connected user,
so the error message is still misleading.
You are right with the errdetail_busy_db(), but that's only true for
8.4, not for earlier versions. In addition that's only true if you
haven't supressed the hints like some scripts do (-q as example).
Bye
--
Andreas 'ads' Scherbaum
German PostgreSQL User Group
European PostgreSQL User Group - Board of Directors
Volunteer Regional Contact, Germany - PostgreSQL Project
PGDay.eu 2009 in Paris, Nov. 6/7, http://www.pgday.eu/