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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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Subject Views Written By Posted
Query optimize on large database 500 Pavel Volkov 07/13/2016 01:40AM
Re: Query optimize on large database 294 Rick James 07/15/2016 05:12PM
Re: Query optimize on large database 298 Pavel Volkov 07/16/2016 04:15AM
Re: Query optimize on large database 283 Peter Brawley 07/16/2016 12:09PM
Re: Query optimize on large database 276 Pavel Volkov 07/16/2016 12:36PM
Re: Query optimize on large database 271 Rick James 07/16/2016 02:46PM
Re: Query optimize on large database 278 Peter Brawley 07/17/2016 11:22AM
Re: Query optimize on large database 266 Pavel Volkov 07/18/2016 04:28AM
Re: Query optimize on large database 257 Peter Brawley 07/18/2016 08:40AM
Re: Query optimize on large database 269 james wang 07/20/2016 04:46AM
Re: Query optimize on large database 255 Pavel Volkov 07/20/2016 08:06AM
Re: Query optimize on large database 274 Rick James 07/20/2016 09:29AM
Re: Query optimize on large database 264 james wang 07/21/2016 04:35AM


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