Re: Index-only scans vs. partially-retrievable indexes - Mailing list pgsql-hackers

From Andrey Borodin
Subject Re: Index-only scans vs. partially-retrievable indexes
Date
Msg-id 462641641227813@sas1-bf93f9015d57.qloud-c.yandex.net
Whole thread Raw
In response to Re: Index-only scans vs. partially-retrievable indexes  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers

> Andrey Borodin <x4mmm@yandex-team.ru> writes:
> 
>> I've tried to toy with the patch and remembered one related caveat.
>> If we have index for both returnable and nonreturnable attributes, IOS will not be choosen:
> 
>> postgres=# create index on t using gist(a gist_trgm_ops) include (a);
>> postgres=# explain select * from t where a like 'z';
>> QUERY PLAN
>> ---------------------------------------------------------------------
>> Index Scan using t_a_a1_idx on t (cost=0.12..8.14 rows=1 width=32)
>> Index Cond: (a ~~ 'z'::text)
>> (2 rows)
> 
> This case is improved by 0002, no?
> 

Uhmm, yes, you are right. Works as expected with the second patch.
I tried first patch against this before writing. But did not expect much from a revert...

Thanks you!

Best regards, Andrey Borodin.



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