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.


On 1/8/2020 10:25 AM, Justin Taylor wrote:
I'm troubleshooting performance of a query. VE is showing a Table Scan, and I don't know why it's doing a Table Scan. It's on joining two views. The JOIN ON is just <> or = conditions. The Optimized Messages tab shows "Debug messages are not available".

Any suggestions on this?


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