Обсуждение: [GENERAL] Get tables ending with numbers

Hi All,

Im trying to get tables ending with numbers (last 8 characters should be numbers).

For example: I have the tables "test_20160215" and "test_20160131" and "test_1". When i run the below sql im not getting any output.

Select relname from pg_class where relname like '%[0-9]'

Can someone please give some idea on this.

Thanks,
Sathesh

Hello Sathesh

> -----Original Message-----
> From: pgsql-general-owner@postgresql.org [mailto:pgsql-general-owner@postgresql.org] On Behalf Of Sathesh S
> Sent: Mittwoch, 15. Februar 2017 07:17
> To: pgsql-general <pgsql-general@postgresql.org>
> Subject: [GENERAL] Get tables ending with numbers
>
> Hi All,
>
> Im trying to get tables ending with numbers (last 8 characters should be numbers).
>
> For example: I have the tables "test_20160215" and "test_20160131" and "test_1". When i run the below sql im not
> getting any output.
>
> Select relname from pg_class where relname like '%[0-9]'

You should use an operator for regexp:

CREATE TABLE test_20160215 (id integer);
CREATE TABLE

SELECT relname FROM pg_class WHERE relname ~ '[0-9]';
    relname
---------------
[snip]
 test_20160215
[snip]

Or

SELECT relname FROM pg_class WHERE relname ~ 'test_[0-9]+$';
    relname
---------------
 test_20160215
(1 row)

Regards
Charles

> Can someone please give some idea on this.
>
> Thanks,
> Sathesh
>

Sathesh S <sathesh.sundaram@hotmail.com> writes:
> Im trying to get tables ending with numbers (last 8 characters should be numbers).

> For example: I have the tables "test_20160215" and "test_20160131" and "test_1". When i run the below sql im not
gettingany output. 

> Select relname from pg_class where relname like '%[0-9]'

> Can someone please give some idea on this.

You're confusing SQL LIKE patterns with POSIX regexp patterns.  "%" is
a wildcard only in the former; "[...]" is special only in the latter.
(The great thing about standards is there are so many to choose from :-()

A correct implementation of your stated requirement is
    where relname ~ '[0-9]$'
or if you want to be picky about "last 8 characters" you could do
    where relname ~ '[0-9]{8}$'
See
https://www.postgresql.org/docs/current/static/functions-matching.html

            regards, tom lane