Hi,

The problem has absolutely nothing to do with DBI. The issue is a performance one with your chosen dbms. If you run the same query using the supplied query tool provided by your vendor (i.e. isql for Sybase ASE), you will see the same problem... namely the query is taking a long time to execute. Your browser or the webserver is timing out on your perl script which is still waiting for your query to return.

How to fix? Depends on your DBMS. Do you have a covering index? Are the SARGS (search arguments) causing a table/index scan or what? This basically becomes a DBMS specific issue as to how to determine the real culprit. Check your dbms documentation

update: DBI has no knowledge of an aliased table name as it just passes it to your dbms. I know of no DBD that will interfere with the use of an aliased table name (if the DBMS supports it).

You will probably want to make sure the indexes are being used on the joining columns....

Jason L. Froebe

No one has seen what you have seen, and until that happens, we're all going to think that you're nuts. - Jack O'Neil, Stargate SG-1


In reply to Re: Does DBI handle table alias? by jfroebe
in thread Does DBI handle table alias? by punch_card_don

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