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ioguix/btree_bloat.sql

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B-tree index bloat estimation
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btree_bloat.sql
/* The bloat estimation queries moved to this respository:
* https://github.com/ioguix/pgsql-bloat-estimation
*/
@darkixion
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The bloat for pg_operator on a database I just looked at returned -80 as the bloat ratio with this query.

@ioguix
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ioguix commented Oct 8, 2014

Hi darkixion,

Sorry for the late answer, I never noticed your comment.

As explained in my various blog posts, this table is using the "name" type, leading to really bad estimations. You have to filter out indexes that we can not have a good estimation using the "is_na" field.

See "Known bug" in http://blog.ioguix.net/postgresql/2014/06/24/More-work-on-index-bloat-estimation-query.html

I should add links to my blog posts as documentation or put these queries in a repository with a proper README at some point...

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