From: | Oleg Bartunov <obartunov(at)gmail(dot)com> |
---|---|
To: | Cory Tucker <cory(dot)tucker(at)gmail(dot)com> |
Cc: | "pgsql-general(at)postgresql(dot)org" <pgsql-general(at)postgresql(dot)org> |
Subject: | Re: Grouping By Similarity (using pg_trgm)? |
Date: | 2015-05-22 09:37:25 |
Message-ID: | CAF4Au4yzCzJ7VnfGhMnY_9BjqzCuGKsxBxaLXrfJtkLeurcU-Q@mail.gmail.com |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-general |
Have you seen http://www.sai.msu.su/~megera/postgres/talks/pgcon-2012.pdf ?
On Thu, May 14, 2015 at 9:58 PM, Cory Tucker <cory(dot)tucker(at)gmail(dot)com> wrote:
> [pg version 9.3 or 9.4]
>
> Suppose I have a simple table:
>
> create table data (
> my_value TEXT NOT NULL
> );
> CREATE INDEX idx_my_value ON data USING gin(my_value gin_trgm_ops);
>
>
> Now I would like to essentially do group by to get a count of all the
> values that are sufficiently similar. I can do it using something like a
> CROSS JOIN to join the table on itself, but then I still am getting all the
> rows with duplicate counts.
>
> Is there a way to do a group by query and only return a single "my_value"
> column and a count of the number of times other values are similar while
> also not returning the included similar values in the output, too?
>
>
From | Date | Subject | |
---|---|---|---|
Next Message | Nicklas Avén | 2015-05-22 09:51:34 | Different result depending on order of joins |
Previous Message | Gilles Darold | 2015-05-22 09:16:03 | Re: date with month and year |