mysql while,loop,repeat循环,符合条件跳出循环_MySQL
1、while循环
DELIMITER $$ DROP PROCEDURE IF EXISTS `sp_test_while`$$ CREATE PROCEDURE `sp_test_while`( IN p_number INT, #要循环的次数 IN p_startid INT #循环的其实值 ) BEGIN DECLARE v_val INT DEFAULT 0; SET v_val=p_startid; outer_label: BEGIN #设置一个标记 WHILE v_val<=p_number DO SET v_val=v_val+1; IF(v_val=100)THEN LEAVE outer_label; #满足条件,终止循环,跳转到end outer_label标记 END IF; END WHILE; SELECT ‘我是while外,outer_label内的SQL‘; #由于这句SQL在outer_label代码块内,所以level后,这句SQL将不会执行; #只要是在outer_label代码块内 任意位置 Leave outer_label,那么Leave后的代码将不再执行 END outer_label; SELECT CONCAT(‘test‘,v_val) AS tname; END$$ DELIMITER ; CALL sp_test_while(1000,0);
2、loop 循环
DELIMITER $$ DROP PROCEDURE IF EXISTS `sp_testloop`$$ CREATE PROCEDURE `sp_testloop`( IN p_number INT, #要循环的次数 IN p_startid INT #循环的其实值 ) BEGIN DECLARE v_val INT DEFAULT 0; SET v_val=p_startid; loop_label: LOOP #循环开始 SET v_val=v_val+1; IF(v_val>p_number)THEN LEAVE loop_label; #终止循环 END IF; END LOOP; SELECT CONCAT(‘testloop_‘,v_val) AS tname; END$$ delimiter ; CALL sp_testloop(1000,0);
3、repeat循环下载地址
DELIMITER $$ DROP PROCEDURE IF EXISTS `sp_test_repeat`$$ CREATE PROCEDURE `sp_test_repeat`( IN p_number INT, #要循环的次数 IN p_startid INT #循环的其实值 ) BEGIN DECLARE v_val INT DEFAULT 0; SET v_val=p_startid; REPEAT #repeat循环开始 SET v_val=v_val+1; until v_val>p_number #终止循环的条件,注意这里不能使用‘;‘分号,否则报错 END repeat; #循环结束 SELECT CONCAT(‘test‘,v_val) AS tname; END$$ DELIMITER ; CALL sp_test_repeat(1000,0);
以上就是mysql while,loop,repeat循环,符合条件跳出循环_MySQL的内容,更多相关内容请关注PHP中文网(www.php.cn)!

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