常用SQL笔记MySQL
2025-04-08 23:42阅读:20评论:0
MySQL之游标
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delimiter $create PROCEDURE phoneDeal()BEGIN DECLARE ids varchar(64); -- 遍历数据结束标志 DECLARE done INT DEFAULT FALSE; -- 游标 DECLARE cur_account CURSOR FOR SELECT id FROM shop_category WHERE pid='0'; -- 将结束标志绑定到游标 DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = TRUE; -- 打开游标 OPEN cur_account; -- 遍历 read_loop: LOOP -- 取值 取多个字段 FETCH NEXT from cur_account INTO ids; IF done THEN LEAVE read_loop; END IF; set @i = (SELECT UUID()); update shop_category set id = @i WHERE id=ids; update shop_category set id=UUID(), pid = @i WHERE pid=ids; END LOOP; CLOSE cur_account;END $ call phoneDeal();