Re: Is it possible to speed up addition of "not null"? - Mailing list pgsql-general

* hubert depesz lubaczewski:

> procedure would look like:
> 1. update pg_attribute set attnotnull = true where attrelid = 'my_table'::regclass and attname = 'not-null-column';
> 2. delete from my_table where not-null-column is null; -- this shouldn't
>    do anything, as I know that there are no null values, but just in
>    case
> 3. pg_reorg of the table.

You could install a trigger before step 1 which prevents INSERTs and
UPDATEs which would add even more rows violating the constraint.

I'm not sure if the DELETE will actually do anything, given that
pg_attribute says that the column cannot be NULL.

--
Florian Weimer                <fweimer@bfk.de>
BFK edv-consulting GmbH       http://www.bfk.de/
Kriegsstraße 100              tel: +49-721-96201-1
D-76133 Karlsruhe             fax: +49-721-96201-99