Re: [martin@bugs.unl.edu.ar: BUG in logs]

I have looked at this behavior, which indeed is new for 8.1.  The change
was caused by code I think I did to improve the behavior of
log_statement, specifically streamlining how we check for the type of
command.

In looking at reverting to the 8.0 behavior of logging error commands
with 'all', I see it is going to be hard to do, specifically since we
added behavior of logging the PREPARE query when EXECUTE is sent.  I
don't think we want to lose that feature, and to have it we have to
first parse the statement, with possible exit on error.

What I have done is to document that errors are not output by
log_statement, and added as suggestion to use log_min_error_statement
for this purpose.  I also fixed the code so the first EXECUTE has it's
prepare, rather than the last which is what was in the current code.

I also removed the "protocol" prefix from the PREPARE output, because in
fact both protocol and SQL-level prepares can be executed by SQL
EXECUTE.

Patch attached.  I have backpatched this to 8.1.X.

---------------------------------------------------------------------------

Martin Marques wrote:
>
> OK, you're right about the log_min_error_statement value, but this behaviour has changed from 8.0. In earlier
versionsERROR statements did get logged if log_statment was set to all or in 7.4, set to "on" DMaybe I missed something
inthe changelog of 8.1? 
>
> On Tue, 11 Apr 2006 23:51:51 +0200, "Guillaume Smet" <guillaume.smet@gmail.com> wrote:
> >> From: Martin Marques <martin@bugs.unl.edu.ar>
> >> I encountered a rare BUG in the way PG is logging. Let me first enlight
> > with some configuration I have and PG version:
> >
> > Perhaps I'm missing something but I think it's not a bug but a
> > configuration problem.
> >
> >>  log_min_error_statement    | panic
> >
> > If you set this one to error instead of panic, you will have your
> > failed statements logged.
> >
> >>  log_statement              | all
> >
> > This one only logs successful queries so it's normal you don't have
> > the statement in the log file if it fails.
> >
> > Regards,
> >
> >
> --
> ---------------------------------------------------------
> Lic. Mart?n Marqu?s         |   SELECT 'mmarques' ||
> Centro de Telem?tica        |       '@' || 'unl.edu.ar';
> Universidad Nacional        |   DBA, Programador,
>     del Litoral             |   Administrador
> ---------------------------------------------------------
>
>
>
> ---------------------------(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
>

--
  Bruce Momjian   http://candle.pha.pa.us
  EnterpriseDB    http://www.enterprisedb.com

  + If your life is a hard drive, Christ can be your backup. +
Index: doc/src/sgml/config.sgml
===================================================================
RCS file: /cvsroot/pgsql/doc/src/sgml/config.sgml,v
retrieving revision 1.52
diff -c -c -r1.52 config.sgml
*** doc/src/sgml/config.sgml    10 Mar 2006 19:10:47 -0000    1.52
--- doc/src/sgml/config.sgml    18 Apr 2006 00:35:12 -0000
***************
*** 2758,2766 ****
         <note>
          <para>
           The <command>EXECUTE</command> statement is not considered a
!          <literal>ddl</> or <literal>mod</> statement.  When it is logged,
!          only the name of the prepared statement is reported, not the
!          actual prepared statement.
          </para>

          <para>
--- 2758,2767 ----
         <note>
          <para>
           The <command>EXECUTE</command> statement is not considered a
!          <literal>ddl</> or <literal>mod</> statement.  Statements that
!          generate errors are not logged.  Set
!          <varname>log_min_error_statement</> to <literal>error</> to
!          log such statements.
          </para>

          <para>
Index: src/backend/tcop/postgres.c
===================================================================
RCS file: /cvsroot/pgsql/src/backend/tcop/postgres.c,v
retrieving revision 1.483
diff -c -c -r1.483 postgres.c
*** src/backend/tcop/postgres.c    4 Apr 2006 19:35:35 -0000    1.483
--- src/backend/tcop/postgres.c    18 Apr 2006 00:35:21 -0000
***************
*** 586,604 ****

          /*
           * For the first EXECUTE we find, record the client statement used by
!          * the PREPARE.
           */
          if (IsA(parsetree, ExecuteStmt))
          {
              ExecuteStmt *stmt = (ExecuteStmt *) parsetree;
              PreparedStatement *entry;

!             if ((entry = FetchPreparedStatement(stmt->name, false)) != NULL &&
                  entry->query_string)
              {
                  *prepare_string = palloc(strlen(entry->query_string) +
!                                       strlen("  [protocol PREPARE:  %s]") - 1);
!                 sprintf(*prepare_string, "  [protocol PREPARE:  %s]",
                          entry->query_string);
              }
          }
--- 586,606 ----

          /*
           * For the first EXECUTE we find, record the client statement used by
!          * the PREPARE.  PREPARE doesn't save the parse tree so we have no
!          * way to conditionally output based on the type of query prepared.
           */
          if (IsA(parsetree, ExecuteStmt))
          {
              ExecuteStmt *stmt = (ExecuteStmt *) parsetree;
              PreparedStatement *entry;

!             if (*prepare_string == NULL &&
!                 (entry = FetchPreparedStatement(stmt->name, false)) != NULL &&
                  entry->query_string)
              {
                  *prepare_string = palloc(strlen(entry->query_string) +
!                                       strlen("  [PREPARE:  %s]") - 2 + 1);
!                 sprintf(*prepare_string, "  [PREPARE:  %s]",
                          entry->query_string);
              }
          }