mysql triggers
DELIMITER $$
CREATE TRIGGER before_workcenters_insert
BEFORE INSERT
ON WorkCenters FOR EACH ROW
BEGIN
DECLARE rowcount INT;
SELECT COUNT(*)
INTO rowcount
FROM WorkCenterStats;
IF rowcount > 0 THEN
UPDATE WorkCenterStats
SET totalCapacity = totalCapacity + new.capacity;
ELSE
INSERT INTO WorkCenterStats(totalCapacity)
VALUES(new.capacity);
END IF;
END $$
DELIMITER ;