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Re: Query optimize on large database
Posted by: Peter Brawley
Date: July 17, 2016 11:22AM

I'm confused, or the query is: it ...

- selects d2.owner_id

- groups by d1.owner_id

- self-joins on artist and title, not owner_id

- restricts d1.owner_id to one value

Grouping by a column that may have just one value makes no sense. Selecting a column that neither aggregates nor is aggregated will return arbitrary results.

In plain English, what is the query requirement?

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