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* Explicit joins
@ 2011-05-05 06:04 Rishabh Kumar Jain <rishabh.widu@yahoo.com>
2011-05-05 17:16 ` Re: Explicit joins Kevin Grittner <Kevin.Grittner@wicourts.gov>
0 siblings, 1 reply; 2+ messages in thread
From: Rishabh Kumar Jain @ 2011-05-05 06:04 UTC (permalink / raw)
To: pgsql-performance
I referred chapter 14.3 of postgres document version 9.0.
explicit joins help the planner in planninng & thus improve performance.
On what relations are explicit joins to be added??
I am getting data from 10 tables in a view.
I don't know on which pair of tables I have to add explicit joins to improve
performance.
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* Re: Explicit joins
2011-05-05 06:04 Explicit joins Rishabh Kumar Jain <rishabh.widu@yahoo.com>
@ 2011-05-05 17:16 ` Kevin Grittner <Kevin.Grittner@wicourts.gov>
0 siblings, 0 replies; 2+ messages in thread
From: Kevin Grittner @ 2011-05-05 17:16 UTC (permalink / raw)
To: pgsql-performance; Rishabh Kumar Jain <rishabh.widu@yahoo.com>
Rishabh Kumar Jain <rishabh.widu@yahoo.com> wrote:
> I am getting data from 10 tables in a view.
> I don't know on which pair of tables I have to add explicit joins
> to improve performance.
There's usually some fairly natural order in terms of understanding
the request. I find it's often good to try to state in words what
data I want to see (*not* how I think I could get that data, but
describe logically which set of data I want), and list the tables in
the order the appear in that description. The description will
naturally tend to include or imply your join conditions and other
selection criteria.
-Kevin
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2011-05-05 06:04 Explicit joins Rishabh Kumar Jain <rishabh.widu@yahoo.com>
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