Re: recreating table and foreign keys - Mailing list pgsql-sql

On Tue, 3 Dec 2002, Tomasz Myrta wrote:

> Hi
> I use Postgresql 7.2.2.
> Sometimes I have to remove a column from my tables (psql):
> 1. alter table master_table rename to x;
> 2. \i tables.sql
> 3. insert into master_table select f1,f2,... from x
> 4. drop table x
>
> I think, foreign keys referring from detail_table(s) to master_table
> have gone.
> How to recreate foreign keys? I want to keep my database in better
> integrity, than now...

You'll probably end up using ALTER TABLE ADD CONSTRAINT to add the
constraints to the new master_table.  It's possible that you might be able
to hack something with the system tables, but that sounds dangerous.  Or
you can upgrade to 7.3 which lets you run alter table drop column. :)