Re: [PATCH] Add extra statistics to explain for Nested Loop - Mailing list pgsql-hackers

From Pavel Stehule
Subject Re: [PATCH] Add extra statistics to explain for Nested Loop
Date
Msg-id CAFj8pRA=wMP+yebbssQByL9nV5FJe6vnkw-ZB7zta1j2W9ftjg@mail.gmail.com
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In response to [PATCH] Add extra statistics to explain for Nested Loop  (e.sokolova@postgrespro.ru)
Responses Re: [PATCH] Add extra statistics to explain for Nested Loop  (Julien Rouhaud <rjuju123@gmail.com>)
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pá 16. 10. 2020 v 9:43 odesílatel <e.sokolova@postgrespro.ru> napsal:
Hi, hackers.
For some distributions of data in tables, different loops in nested loop
joins can take different time and process different amounts of entries.
It makes average statistics returned by explain analyze not very useful
for DBA.
To fix it, here is the patch that add printing of min and max statistics
for time and rows across all loops in Nested Loop to EXPLAIN ANALYSE.
Please don't hesitate to share any thoughts on this topic!

+1

This is great feature - sometimes it can be pretty messy current limited format

Pavel

--
Ekaterina Sokolova
Postgres Professional: http://www.postgrespro.com
The Russian Postgres Company

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