On Tue, 2007-02-06 at 14:06 -0500, Merlin Moncure wrote: > On 2/6/07, Mark Lewis <mark.lewis@xxxxxxxx> wrote: > > > actually, I get the stupid award also because RI check to unindexed > > > column is not possible :) (this haunts deletes, not inserts). > > > > Sure it's possible: > > > > CREATE TABLE parent (col1 int4); > > -- insert many millions of rows into parent > > CREATE TABLE child (col1 int4 REFERENCES parent(col1)); > > -- insert many millions of rows into child, very very slowly. > > the database will not allow you to create a RI link out unless the > parent table has a primary key/unique constraint, which the database > backs with an index....and you can't even trick it afterwards by > dropping the constraint. > > it's the other direction, when you cascade forwards when you can have > a problem. this is most common with a delete, but can also happen on > an update of a table's primary key with child tables referencing it. > Hmmm, should check my SQL before hitting send I guess. Well, at least you no longer have to wear the stupid award, Merlin :) -- Mark Lewis
