Re: get column default value

Jean-Christophe Roux wrote:
> I understand that but I need to build an interface so that my user can
> change the default values of some table/columns. So I need a way to
> query the current default value to show the user what it is currently.
> For instance, let's say I have a table products and there is a column
> price and the default price is $199, I'd like to get that $199 and
> give my user the opportunity to update that value. The column does not
> have any sequence attached to it.
> JCR
>
> ----- Original Message ----
> From: Ketema Harris <ketema@gmail.com>
> To: Jean-Christophe Roux <jcxxr@yahoo.com>
> Cc: pgsql-php@postgresql.org
> Sent: Monday, November 13, 2006 9:59:29 AM
> Subject: Re: [PHP] get column default value
>
> The default value for a column is just that the value you say is
> default.  It only come into play when you do an insert into the
> table.  If you do not provide a value for that column then your
> default value is entered.
>
> Now if you set the default value of a column to a sequence, then you
> can manage the sequence using the sequence functions: currval,
> nextval, and setval.  Sequences and their functions are documented in
> the pg manual.
>
> On Nov 13, 2006, at 9:49 AM, 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
>
SELECT adsrc as default_value
FROM pg_attrdef pad, pg_atttribute pat, pg_class pc
WHERE pc.relname='your_table_name'
    AND pc.oid=pat.attrelid AND pat.attname='your_column_name'
    AND pat.attrelid=pad.adrelid AND pat.attnum=pad.adnum

--
erik jones <erik@myemma.com>
software development
emma(r)