I have 2 tables params and params_exceptions where params is supposed to be updated frequently by an external script.
INSERT INTO params (extension, type, subtype, paramvalue) VALUES ('12345', 'FRNR1', 'FORWARD', '24268') ON DUPLICATE KEY UPDATE paramvalue = VALUES(paramvalue);
The purpose is that params_exceptions contains records which prevents certain records in params to be updated with the new data (or using the data in params_exceptions afterwards for that record).
I've been messing around a bit and I was thinking of combining WHERE NOT EXISTS within the ON DUPLICATE KEY UPDATE? Of course all of the above is possible by using sequential statements, but it's possible that the script would run at the same time and I can't use transactions for now.
I was thinking of the following statement, but I can't seem to figure it out:
INSERT INTO params (extension, type, subtype, paramvalue) SELECT * FROM (SELECT '12345', 'TEST', 'TEST2', '24268') AS tmp WHERE NOT EXISTS ( SELECT 1, extension FROM params_exceptions t WHERE extension = '12345' AND type = 'FRNR1' AND subtype = 'FORWARD' ) LIMIT 1 ON DUPLICATE KEY UPDATE subtype=subtype, paramvalue=t.extension;
Can someone give me some advice here?