mysql triggers

1CREATE TRIGGER trigger_name
2{BEFORE | AFTER} {INSERT | UPDATE| DELETE }
3ON table_name FOR EACH ROW
4trigger_body;

1
2        
3            
4        
5     DELIMITER $$
6
7CREATE TRIGGER before_workcenters_insert
8BEFORE INSERT
9ON WorkCenters FOR EACH ROW
10BEGIN
11    DECLARE rowcount INT;
12    
13    SELECT COUNT(*) 
14    INTO rowcount
15    FROM WorkCenterStats;
16    
17    IF rowcount > 0 THEN
18        UPDATE WorkCenterStats
19        SET totalCapacity = totalCapacity + new.capacity;
20    ELSE
21        INSERT INTO WorkCenterStats(totalCapacity)
22        VALUES(new.capacity);
23    END IF; 
24
25END $$
26
27DELIMITER ;
28