本文中的存储过程示例，预计的循环次数是yh表行数，由于SELECT IID INTO PINT FROM YH WHERE 0=1;不返回任何行，所以at_end后会立刻等于1（只循环一次就退出）。
DECLARE at_end INT DEFAULT 0; DECLARE PIID INTEGER DEFAULT 0 ;DECLARE PINT INTEGER DEFAULT 0 ; DECLARE not_found CONDITION FOR SQLSTATE '02000';--DECLARE PCOUNT INTEGER;DECLARE c1 CURSOR FOR SELECT IID FROM YH; DECLARE CONTINUE HANDLER FOR not_found SET at_end = 1; OPEN c1; SET PCOUNT=0;ins_loop: LOOP FETCH c1 INTO PIID; IF at_end <>0 THEN LEAVE ins_loop; END IF; SET PCOUNT=PCOUNT+1;SELECT IID INTO PINT FROM YH WHERE 0=1;END LOOP;
