Scott Marlowe wrote:
You can't change a table in any way without rewriting the whole thing, resulting in a very long wait and a complete table lock on any alter table action on big tables. Don't forget that if you've got a really big table, you need that much space free on the drive to alter the table for the rewrite that's going to take place.
Forgive a dumb question: What does postgresql do with ALTER TABLE? What sort of modifications do not require time proportional to the number of rows in the table? Jack Orenstein
