Difference between revisions of "PostgreSQL VACUUM"

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PostgreSQL [[VACUUM]] [[garbage-collect]] and optionally analyze a database.
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* https://www.postgresql.org/docs/current/sql-vacuum.html
  
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VACUUM reclaims storage occupied by dead [[tuples]].
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== Examples ==
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* <code>VACUUM (VERBOSE, [[ANALYZE]]) my_table;</code>
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* <code>[[VACUUM FULL]] my_table;</code>
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SELECT
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  schemaname, relname,
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  last_vacuum, last_autovacuum,
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  vacuum_count, autovacuum_count
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FROM [[pg_stat_user_tables]];
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[[select count]](*) from [[pg_stat_activity]] where query like '[[autovacuum]]:%';
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PosgreSQL recommend that active production databases be vacuumed frequently (at least nightly), in order to remove dead rows. <ref>https://www.postgresql.org/docs/current/sql-vacuum.html</ref>
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VACUUM causes a substantial increase in [[I/O]] traffic.
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== News ==
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* [[PostgreSQL 13]] (Oct 2020) parallelized vacuuming of [[indexes]]
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== Logs ==
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2023-07-10 10:01:39 UTC [520415]: LOG: skipping [[vacuum]] of "your_test" --- [[lock not available]]
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== Related terms ==
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* [[GIN]] indexes
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* [[Autovacuum]]
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* [[Tuple]]
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* [[Redshift VACCUM]]
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* "plain" VACCUM
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* [[Index Locking]]
  
 
== See also ==
 
== See also ==
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* {{VACUUM}}
 
* {{PostgreSQL}}
 
* {{PostgreSQL}}
  
 
[[Category:PostgreSQL]]
 
[[Category:PostgreSQL]]

Latest revision as of 10:32, 11 July 2023

PostgreSQL VACUUM garbage-collect and optionally analyze a database.

VACUUM reclaims storage occupied by dead tuples.


Examples[edit]

SELECT
  schemaname, relname,
  last_vacuum, last_autovacuum,
  vacuum_count, autovacuum_count
FROM pg_stat_user_tables;
select count(*) from pg_stat_activity where query like 'autovacuum:%';


PosgreSQL recommend that active production databases be vacuumed frequently (at least nightly), in order to remove dead rows. [1]

VACUUM causes a substantial increase in I/O traffic.

News[edit]

Logs[edit]

2023-07-10 10:01:39 UTC [520415]: LOG: skipping vacuum of "your_test" --- lock not available

Related terms[edit]

See also[edit]

  • https://www.postgresql.org/docs/current/sql-vacuum.html
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