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Large query - multiple datasets? [message #529534]

Mon, 26 April 2010 09:55

Missing name Missing name

Messages: 94
Registered: November 2009

Member

Hi,
I have a fairly big query that I would like to break up into more manageable/testable sections. I could create DB views but would prefer not to, if possible, as we support 3 databases so it would mean a bit more work.
i am thinking of breaking the query up into multiple datasets and joining them using a joint dataset, would this approach recommended? All of the datasets would be connected to the same datasource. Would there be any (noticeable) performance hit in this approach, or can someone recommend a better way to split a big query?

thanks
Trevor

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Re: Large query - multiple datasets? [message #529651 is a reply to message #529534]

Mon, 26 April 2010 16:05

Richard A. Polunsky

Messages: 212
Registered: July 2009
Location: Houston TX

Senior Member

I strongly urge you to reconsider. Joint datasets are not built for performance, they exist apparently to fulfill the need of joining data that comes from disparate sources. If you have a complex query, you really need to utilize the engine of your database.

If you need to test in smaller sections, then factor your query and break it out into logically separate pieces (then rebuild it as appropriate).

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