# $Id: memoserv.3.sql,v 1.1.1.1 2005/08/27 15:44:49 jpinto Exp $
# First remove the NOT NULL from sender
ALTER TABLE memoserv
CHANGE sender_snid sender_snid INT UNSIGNED NULL;
# Update the sender if null
UPDATE memoserv SET sender_snid=NULL WHERE sender_snid=0;
# Add the foreign keys
ALTER TABLE memoserv
ADD CONSTRAINT FK_MS1 FOREIGN KEY (owner_snid) REFERENCES nickserv (snid)
ON DELETE CASCADE ON UPDATE CASCADE;
ALTER TABLE memoserv
ADD CONSTRAINT FK_MS2 FOREIGN KEY (sender_snid) REFERENCES nickserv (snid)
ON DELETE SET NULL ON UPDATE CASCADE;
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