Date: Tue, 25 Mar 2003 12:32:03 -0800
From: patrick <patrick+pgsql@boxsoft.com>
To: Roy Souther <roy@SiliconTao.com>
Cc: pgsql-sql@postgresql.org
Subject: Re: Insert race hazard condition.
Message-ID: <20030325123203.I255@3eye.boxsoft.com>
References: <1048622477.2643.44.camel@UtopiaPlanetia.Ept>
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	from roy@SiliconTao.com on Tue, Mar 25, 2003 at 01:01:17PM -0700

On Tue, Mar 25, 2003 at 01:01:17PM -0700, Roy Souther wrote:
> First of all I am a programmer not an DBA expert. 
> 
> For a long time now when I create a table I have an index field that is
> of type int4 to be the primary key. All of the queries and activity on
> each record uses this field to do the posting, manipulating and reading
> of data to and from tables.
> 
> When I add a record to a table I would do it in two steps.
> INSERT INTO mytable SELECT MAX(index)+1 FROM mytable
> SELECT MAX(index) FROM mytable


You probably want to call:

  Oid oid = PQoidValue( res ); /* assuming C interface */

And use:

  sprintf( sql, "select index from mytable where oid = %lu", oid );

instead of your second SQL statement.

[dd]

sidster
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