[GENERAL] WinXP - statistics collector errors
Hello, In my log files I have an error that occurs frequently : FATAL: could not read from statistics collector pipe and FATAL: could not write to statistics collector pipe: No connection could be made because the target machine actively refused it. The server release is 8.0.3 and is running on WinXP Pro sp2 The pg_autovacuum deamon is running (if it can help...) I would appreciate any help. I wonder if this error is really "FATAL" or not. ---(end of broadcast)--- TIP 9: In versions below 8.0, the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match
[GENERAL] pg_dump, MVCC and consistency
Hello everybody ! I am coming from the (expensive) "Oracle World" and I am a newbie in PG administration. I am currently working on backup concerns... I am using pg_dump and I have not encountered any problems but I have some questions about the internal management of data consistency in PG server. I have read some articles about the MVCC mechanism but I can't see how it handles a consistent "snapshot" of the database during all the export process. If I have well understood, the defaut transaction isolation level in PG is the "read commited" isolation level. If it is the isolation scheme used by pg_dump how can I be sure that tables accessed at the end of my export are consistent with those accessed at the begining ? Does pg_dump use a serializable isolation scheme ? We have this kind of concerns with Oracle and a "CONSISTENT" flag can be set in the exp utility to use a consistent snapshot of the database from the begining to the end of the export process. Unfortunately, this mode use intensively rollback segments and can drive to obsolete data (also knows as "Snapshot too old"). Is there the equivalent of rollback segments in PG ? Is there some issues like "snapshot too old" with intensive multi-users and transactional databases ? I have not a good knowledge of PG internal mechanism, I hope that my questions are clear enough... Florian ---(end of broadcast)--- TIP 5: don't forget to increase your free space map settings
[GENERAL] autovacuum deamon on 8.0.3 - WinXP
Hello, An autovacuum deamon has been installed as a Windows service during the setup of my PG 8.0.3 server on WinXP. I am surprised because I believed that autovacuum was only available in 8.1 server. There is no autovacuum_XXX parameters in postgresql.conf... How can I be sure that autovacuum is correctly working ? If it is the case, how is it configured ? Can I rely on this service or have I to periodicaly launch vacuumdb instead ? Can anybody help me... Thanks ---(end of broadcast)--- TIP 5: don't forget to increase your free space map settings
[GENERAL] How to track exceptions in PL/pgSQL
Hello, I would like to track (timestamp and error number) in the database or in text files the exceptions that occur in my PL/pgSQL functions. 1. How can I retrieve the SQLCODE in a 8.0.3 PG server ? 2. How can I trace the exception in a table although an implicit rollback is done when a exception occurs (the trace will be rollbacked too) ? Thanx ---(end of broadcast)--- TIP 9: In versions below 8.0, the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match
[GENERAL]
Hello, Having freshly installed a PG database (8.0.3), I have difficulties in tracing exceptions in my PL/pgSQL functions. All my functions implement a BEGIN-EXCEPTION-END block in which exceptions must be traced : BEGIN -- Some stuff EXCEPTION WHEN OTHERS THEN -- trace END; I would like to trace the SQLCODE that triggers the exception. I have heard about a SQLSTATE variable but it doesn't seem to be implemented in the 8.0.3 but only in the 8.1 (not stable release and so not a good choice in a professional context...). How can I get this information ? Is there a patch available ? Is there a workaround ? Thanks ---(end of broadcast)--- TIP 9: In versions below 8.0, the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match
