Re: Postgres 9 : - How to interpret the EXPLAIN query results

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От Anthony Nowocien
Тема Re: Postgres 9 : - How to interpret the EXPLAIN query results
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Msg-id CAH5RRoPEumqBmNX+piExXk3NOKg0vu6fJ3MDGc9J=jfU2y9-rg@mail.gmail.com
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Ответ на Postgres 9 : - How to interpret the EXPLAIN query results  (Khangelani Gama <kgama@argility.com>)
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Hi,
everything you need to know is available on the documentation at http://www.postgresql.org/docs/current/static/sql-explain.html.

"COSTS

Include information on the estimated startup and total cost of each plan node, as well as the estimated number of rows and the estimated width of each row. This parameter defaults to TRUE."

Best regards,
Anthony

On Wed, Mar 25, 2015 at 9:00 AM, Khangelani Gama <kgama@argility.com> wrote:

Hi

 

Please help, how can I interpret the following results of my EXPLAIN query ?, I can see that the query will through 18586018 rows, but what’s the meaning of cost and width?

 

GroupAggregate  (cost=762381141.96..768375132.77 rows=18586018 width=32)

 

 

 

 

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