>
> how can I alter the column width
>
Something like
begin ;
alter table foo rename column b to b_old ;
alter table foo add column b_new character(20) ;
update foo set b_new = b_old ;
alter table foo drop column b_old ;
alter table foo rename column b_new to b ;
commit ;
does the trick. Refer to the archives too.
Regards, Christoph