Re: JOIN on partitions is very slow - Mailing list pgsql-performance

From daya airody
Subject Re: JOIN on partitions is very slow
Date
Msg-id CAFg0VMAkUn7AJuNo28sm2zXcsJUXKm+ACD2CmZZxZ801PZSiPw@mail.gmail.com
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In response to Re: JOIN on partitions is very slow  (Michael Lewis <mlewis@entrata.com>)
Responses Re: JOIN on partitions is very slow  (Michael Lewis <mlewis@entrata.com>)
List pgsql-performance
Yes. I can tweak the query. Version of postgres is 9.5.15. I have about 20 partitions for company_sale_account table. 
I do have an index on company name.

I need to use DISTINCT as i need to remove the duplicates.

Thanks for your time.



On Sun, Mar 22, 2020 at 11:38 PM Michael Lewis <mlewis@entrata.com> wrote:
Are you able to tweak the query or is that generated by an ORM? What version of Postgres? Which configs have you changed from default? How many partitions do you have? Is there an index on company name?

Anytime I see distinct keyword, I expect it to be a performance bottleneck and wonder about rewriting the query. Even just using group by can be much faster because of how it gets executed.

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