sybperl-l Archive

From: Michael Peppler <mpeppler at peppler dot org>
Subject: Re: DBD::Sybase 0.17 and AutoCommit == 0
Date: Jun 2 1999 2:33PM

Tim Bunce writes:
 > On Tue, Jun 01, 1999 at 04:31:44PM -0700, Michael Peppler wrote:
 > >     *** From dbi-dev -- To unsubscribe, see the end of this message. ***
 > > 
 > > Starting with DBD::Sybase 0.15 I've changed the way I handle
 > > AutoCommit off mode.
 > > In previous versions, DBD::Sybase would issue a BEGIN TRAN 
 > > if needed, and $dbh->commit would issue a COMMIT TRAN .
 > > The current version uses the SET CHAINED option. When the CHAINED
 > > option is on the Sybase server automatically acts as if a BEGIN TRAN
 > > was issued, and will only effectively commit the changes once a COMMIT 
 > > is sent.
 > 
 > What were the down-sides, if any, to the previous approach?

DDL statements (such as creating a temporary table) which can be
hidden in stored procedure can't be used inside an explicit
transaction, unless one sets the ddl_in_transactions option to true
(because this causes long lived locks on system tables, not a good
thing). 

When using the CHAINED TRANSACTIONS option this feature works (but at
the expense of nested transactions, rats!)

So it looks like 6 of one or a half-dozen of the other...

 > 
 > Perhaps you could make it configurable and default it to off
 > (for maximum compatibility). Those who would benefit from it can
 > enable it if they choose:
 > 
 > 	DBI->connect(..., { syb_chained_txn => 1 });

Yeah - look for this in 0.18.

Michael