Re: get column default value

[Rick Morris <rick(at)brainscraps(dot)com>]

Jean-Christophe Roux wrote:
> Hello,
> How can I get the default value for a column?
> To change the default value, something like
> ALTER TABLE dummy ALTER COLUMN value SET DEFAULT -12;
> would do the job, but how could I query the value?
>
>
> Thanks in advance
You can select from the pg_ system tables, but there is now an easier 
method with PostgreSQL 7.4+.

What you want is the (redundantly-named) "information_schema" schema in 
any PostgreSQL database. I take it you have installed phpPgAdmin 
(phppgadmin.sf.net)? Then just open it and navigate to 
information_schema inside your database, and look for the View titled 
'columns', and a column titled 'column_default'. So your query would 
look something like:

SELECT column_default FROM information_schema.columns WHERE 
table_name='your_table_name';

or if needed:

SELECT column_default FROM information_schema.columns WHERE 
table_name='your_table_name' AND schema='whatever_schema';

(this would be needed if you have a duplicate table name in more than 
one schema)

HTH,

Regards,

Rick Morris