drop procedure if existsP_SEQUENCE;/** 暂省略包@AUTO LIANGRUI 2014/6/27T_PRO_PRODUCT 表 排序 对整个表进行按序号排序 根据序号从新自然排序 重复序号的安创建日期分配序号 测试阶段测试调用 set @merid='TEST66'; call P_SEQUENCE(@merid); **/create procedure P_PRODUCT_SEQUENCE( in v_merchar_id VARCHAR(100)) beginDECLARE v_idVARCHAR(100);DECLARE v_rowNo VARCHAR(100);DECLARE flag int;DECLARE e_error INTEGER DEFAULT 0;-- 定义游标 DECLARE c_cur CURSORforSelect a.id ,(@rowNum:=@rowNum+1) as rowNoFrom T_PRO_PRODUCT a ,(Select (@rowNum :=0)) bwhere MERCHANT_ID=v_merchar_idorder by ISNULL(a.sequence),a.sequence,a.create_dt; DECLARE CONTINUE HANDLER FOR NOT FOUND SET flag=1;DECLARE CONTINUE HANDLER FOR SQLEXCEPTION SET e_error=1;SET flag=0;OPEN c_cur;-- 循环所有的行 REPEATFETCH c_cur INTO v_id,v_rowNo; update T_PRO_PRODUCT SET sequence= v_rowNo where ID=v_id; -- 循环结束UNTIL flag END REPEAT; -- 关闭游标 CLOSEc_cur; -- 事务处理 IF e_error = 1 THEN ROLLBACK; ELSE COMMIT; END IF;end
上面的其实可以进行简化
SET @colNo = 0;
UPDATE T_PRO_PRODUCT SET SEQUENCE=(@colNo:=@colNo+1) WHERE MERCHANT_ID='TEST66' ORDER BY SEQUENCE, CREATE_DT DESC;

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MySQL is suitable for beginners because it is simple to install, powerful and easy to manage data. 1. Simple installation and configuration, suitable for a variety of operating systems. 2. Support basic operations such as creating databases and tables, inserting, querying, updating and deleting data. 3. Provide advanced functions such as JOIN operations and subqueries. 4. Performance can be improved through indexing, query optimization and table partitioning. 5. Support backup, recovery and security measures to ensure data security and consistency.


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