Re: How to speed up product code and subcode match - Mailing list pgsql-general

From Andrus
Subject Re: How to speed up product code and subcode match
Date
Msg-id ca7c9dde-be23-46c2-227f-50a5f35e9b21@hot.ee
Whole thread Raw
In response to Re: How to speed up product code and subcode match  (Andrus <kobruleht2@hot.ee>)
List pgsql-general

Hi!

Using index

create index on toode ( split_part( toode, '/',1) )

and query

select toode.toode , n2, n3, n4

from toode, vordlusajuhinnak

where split_part( toode.toode, '/',1) = vordlusajuhinnak.toode;

reduces run time to 5 minutes.

Andrus.


23.05.2023 17:26 Andrus kirjutas:

Hi!

Separate
the product code and size into two columns --- if there's somebody
who really wants to see them in the above format, give them a
view or generated column.  Then instead of the impossible-to-optimize
queries you showed, you could do something like

select toode.toode , n2, n3, n4
from toode, vordlusajuhinnak
where toode.toode = vordlusajuhinnak.toode;

Can function index

create index on toode ( split_part( toode, '/',1) )

and query

select toode.toode , n2, n3, n4

from toode, vordlusajuhinnak

where split_part( toode.toode, '/',1) = vordlusajuhinnak.toode;
used and keeping existing table structure? Functional index should produce same speed improvement as using separate column?

Andrus.

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