Re: Fuzzy substring searching with the pg_trgm extension

From: Artur Zakirov <a(dot)zakirov(at)postgrespro(dot)ru>
To: Alvaro Herrera <alvherre(at)2ndquadrant(dot)com>
Cc: Jeff Janes <jeff(dot)janes(at)gmail(dot)com>, pgsql-hackers <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: Fuzzy substring searching with the pg_trgm extension
Date: 2016-01-21 09:15:45
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On 21.01.2016 00:25, Alvaro Herrera wrote:
> Artur Zakirov wrote:
>> Added GUC variables:
>> - pg_trgm.limit
>> - pg_trgm.substring_limit
>> I added this variables to the documentation.
>> show_limit() and set_limit() functions work correctly and they are marked as
>> deprecated.
> Thanks. I'm willing to commit quickly a small patch that only changes
> the existing function to GUCs, then have a look at a separate patch that
> adds the new substring operator. Would you split the patch that way?

Sure. I attached two patches. But notice that pg_trgm.limit should be
used with this command:

SHOW "pg_trgm.limit";

If you will use this command:

SHOW pg_trgm.limit;

you will get the error:

ERROR: syntax error at or near "limit"
LINE 1: SHOW pg_trgm.limit;

This is because "limit" is keyword I think.
If it is important then GUC variables can have names:

- pg_trgm.sml_limit
- pg_trgm.substring_sml_limit

Artur Zakirov
Postgres Professional:
Russian Postgres Company

Attachment Content-Type Size
pg_trgm_guc.patch text/x-patch 5.8 KB
pg_trgm_substring_v4.patch text/x-patch 181.4 KB

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