Re: timeout implementation issues

Bruce Momjian <pgman@candle.pha.pa.us>

From: Bruce Momjian <pgman@candle.pha.pa.us>
To: Hiroshi Inoue <Inoue@tpf.co.jp>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, Jan Wieck <janwieck@yahoo.com>, Jessica Perry Hekman <jphekman@dynamicdiagrams.com>, Barry Lind <barry@xythos.com>, pgsql-hackers@postgresql.org
Date: 2002-04-09T00:45:46Z
Lists: pgsql-hackers
Hiroshi Inoue wrote:
> Bruce Momjian wrote:
> > 
> > Hiroshi Inoue wrote:
> > > > > Why should the SET query_timeout = 0 command be issued
> > > > > only when the query failed ? Is it a JDBC driver's requirement
> > > > > or some applications' requirements which uses the JDBC driver ?
> > > >
> > > > They want the timeout for only the one statement, so they have to set it
> > > > to non-zero before the statement, and to zero after the statement.
> > >
> > > Does setQueryTimeout() issue a corresponding SET QUERY_TIMEOUT
> > > command immediately in the scenario ?
> > 
> > Yes.  If we don't make the SET rollback-able, we have to do all sorts of
> > tricks in jdbc so aborted transactions get the proper SET value.
> 
> In my scenario, setQueryTimeout() only saves the timeout
> value and issues the corrsponding SET QUERY_TIMEOUT command
> immediately before each query if necessary.

Yes, we can do that, but it requires an interface like odbc or jdbc.  It
is hard to use for libpq or psql.

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