[TransWarp] Re: PROPOSAL: drop requirement for 'joinTxn=True' on SQL exec

Ulrich Eck ueck at net-labs.de
Fri Mar 7 05:39:08 EST 2003


> So, to resolve this issue, I propose to make the creation of a cursor always cause an SQL connection to join its
> transaction (thus invoking a 'BEGIN TRANSACTION' statement if appropriate for the type of DB).  In cases where
> holding long read locks might be an issue, this should be resolved by either 1) using the appropriate clause as part
> of the SELECT, 2) a 'SET ISOLATION' statement beforehand, or 3) using a separate connection configured for a
> different isolation level.
>
> These workarounds for the "long select read lock" problem should all be adequate for the situations Ty and I have
> encountered where it occurs, and they do not impose an arbitrary burden on users of MVCC databases such as PostgreSQL
> and Oracle.
>
> If there are no objections, then when I change the transaction-join behavior I will also remove the "joinTxn" binding
> from the SQLCursor class, so that using the 'joinTxn' flag will cause an error, thus conveniently showing you where
> to remove this un-PEAKish wart from your code.  :)

+2



Ulrich Eck
------------------------------------------------------------------------
net-labs Systemhaus GmbH
Ebersberger Str. 46
85570 Markt Schwaben
fon:   +49-8121-4747-11
fax:   +49-8121-4747-77
email: ueck at net-labs.de
http://www.net-labs.de




More information about the PEAK mailing list