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Thread: How can I select a comment on a column?

How can I select a comment on a column?

From
Serguei Pronkine
Date:
Hi community,
I'd like to retrieve comments on tables an columns by table name and
column name. The posting by Tom Lane <tgl ( at ) sss ( dot ) pgh ( dot )
pa ( dot ) us>
http://archives.postgresql.org/pgsql-novice/2004-01/msg00180.php?adv=1
says how to select comment on a column.

regression=# create table mytab (mycol int);
CREATE TABLE
regression=# comment on column mytab.mycol is 'my comment';
COMMENT
regression=# select col_description('mytab'::regclass, 1);
  col_description
-----------------
  my comment
(1 row)


How can I now retrieve column number from column name?

Thanks in advance,
Serguei Pronkine

Re: How can I select a comment on a column?

From
Michael Fuhr
Date:
On Mon, Mar 26, 2007 at 04:37:59PM +0200, Serguei Pronkine wrote:
> How can I now retrieve column number from column name?

Query pg_attribute.

http://www.postgresql.org/docs/8.2/interactive/catalog-pg-attribute.html

Since psql can display object comments you could study the SQL that
it executes:

\set ECHO_HIDDEN
\d+ mytab

--
Michael Fuhr