Re: Evolving databases (eg deleting columns) - Mailing list pgsql-general

On Thu, 2002-07-25 at 20:19, Christian H. Stork wrote:
> My question: How can I evolve databases (ie deleting columns,
> adding/changing/removing constraints, etc)?
PostgreSQL doesn't support deleting columns (I've had this issue myself
recently).  However, there is a workaround.  It is described at:
http://postgresql.org/docs/faq-english.html#4.4

It states:


4.4) How do you remove a column from a table?
We do not support ALTER TABLE DROP COLUMN, but do this:

    BEGIN;
    LOCK TABLE old_table;
    SELECT ...  -- select all columns but the one you want to remove
    INTO TABLE new_table
    FROM old_table;
    DROP TABLE old_table;
    ALTER TABLE new_table RENAME TO old_table;
    COMMIT;

I hope this helps.
--
Kevin Breit <mrproper@ximian.com>