Tom Lane <t...@sss.pgh.pa.us> writes: > Robert Haas <robertmh...@gmail.com> writes: >> Right. If there were a DEFAULT on the new column that would of course >> be different, and you can also do thinks like CHECK (a != b) here. >> However, if the CHECK constraint does not reference any column other >> than the newly-added one, and if the new column will have the same >> value for every row either because there is no default or because the >> default is a constant, > > ... and if the CHECK expression is immutable ...
Doesn't it have to be already? Otherwise a value accepted at one point in time could suddenly violate the constraint later, even though it never changed. ilmari -- "A disappointingly low fraction of the human race is, at any given time, on fire." - Stig Sandbeck Mathisen -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
