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  3. January 2020

RE: Why Table Scan?

I don't think an exception join would be practical. There are 12 conditions (all AND). All but one are = with only a single <>.

Thanks



-----Original Message-----
From: Vernon Hamberg [mailto:vhamberg@xxxxxxxxxxxxxxx]
Sent: Wednesday, January 08, 2020 11:39 AM
To: Midrange Systems Technical Discussion <midrange-l@xxxxxxxxxxxxxxxxxx>
Subject: Re: Why Table Scan?

Hi Justin

<> will often trigger a table scan, even if there are indexes on the tables. There's a section in the VE output with reasons for the choices the optimizer made, as I recall. And suggestions for indexes.

Can you replace the <> with an exception join? It might have better luck.

There is also considerable help in that application for the performance options in a query.

HTH
Vern

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