Re: BUG #4689: Expanding the length of a VARCHAR column should not induce a table rewrite

xuan--2009.03--submitbug--support--postgresql.org@baldauf.org wrote:
> When executing
> "ALTER TABLE sometable ALTER COLUMN somecolumn TYPE VARCHAR(7)", the whole
> table is re-written, and this rewrite takes many hours. During these hours,
> all writers on this table stall, making the database effectively
> unavailable.
>
> However, in almost all cases, there is no need for such relaxing of limits
> to require a table rewrite.

While this isn't a bug, it's a reasonable feature request. I've added
this to the TODO page: http://wiki.postgresql.org/wiki/Todo#ALTER

Patches are welcome.

--
   Heikki Linnakangas
   EnterpriseDB   http://www.enterprisedb.com