Subject | Re: [firebird-support] 20 minute query in v 2.0 and 2.1 |
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Author | Arno Brinkman |
Post date | 2007-05-24T22:09:42Z |
Hi,
for every record in detailTable. I don't see the use of the DISTINCT function in a EXISTS predicate
thus i would remove that one and see what speed is then.
Regards,
Arno Brinkman
ABVisie
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
General database development support:
http://www.databasedevelopmentforum.com
Firebird open source database (based on IB-OE) with many SQL-99 features :
http://www.firebirdsql.org
http://www.firebirdsql.info
http://www.fingerbird.de/
http://www.comunidade-firebird.org/
Support list for Firebird and Interbase users :
firebird-support@yahoogroups.com
Nederlandse firebird nieuwsgroep :
news://newsgroups.firebirdsql.info
> We have a query that is fast in the FB 2.0 RC version, but in 2.0 andThe DISTINCT will cause that the sub-select is first executed fully and sorted afterwards and that
> 2.1 takes 20 minutes. Essentially it deletes all records from a table
> in a master detail relationship.
> something like delete from detailTable where not exists (select distict
> masterTable.ID from masterTable where mastertableID = detailTable.FK)
for every record in detailTable. I don't see the use of the DISTINCT function in a EXISTS predicate
thus i would remove that one and see what speed is then.
Regards,
Arno Brinkman
ABVisie
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
General database development support:
http://www.databasedevelopmentforum.com
Firebird open source database (based on IB-OE) with many SQL-99 features :
http://www.firebirdsql.org
http://www.firebirdsql.info
http://www.fingerbird.de/
http://www.comunidade-firebird.org/
Support list for Firebird and Interbase users :
firebird-support@yahoogroups.com
Nederlandse firebird nieuwsgroep :
news://newsgroups.firebirdsql.info