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Re: Sybase IQ taking unexpectedly long to start query execution

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Thank you very much for your response. The query I am running is a simple select query on a Union all view (no joins just simple selects on similar tables unioned together).

 

I have also run queries on individual tables used in that view and they are also slower than expected. A single table takes a couple of seconds in white space/optimization time, while the actual execution time is just a few ms. I am not sure what it could be optimizing that could take that long, as the queries were just a simple select (Ive tried with and without conditions).

 

It seems that in the Union All View the optimization time is: Optimization time of each table * Number of tables (since that is being done on a single thread). The reason I think there might be a problem is because on some occasions the same queries returned in less than a second for View and just about 400ms for individual tables.

 

The Sybase IQ version I'm using is 15.


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