mysql 存储过程案列一个。

时间:2024-01-09 21:32:32
-- 设置分隔符
DELIMITER // /*初始化*/
DROP PROCEDURE IF EXISTS useCursor // /*建立 存储过程 create */
CREATE PROCEDURE useCursor(input_planGuid BIGINT )
BEGIN -- 声明游标使用的变量----------
DECLARE nowID BIGINT;-- 本行自增id
DECLARE nowGuid BIGINT;-- 本行的guid,
DECLARE parentGuid BIGINT;-- 本行父级guid
DECLARE newIndex BIGINT;-- 要设置的本行的index DECLARE preIndex BIGINT DEFAULT -1;-- 上一行设置的index.
DECLARE preParentGuid BIGINT DEFAULT -1;-- 上一行的父级guid -- 声明游标,从临时表中读取数据.循环更新临时表-----------------------------------------------
DECLARE cur1 CURSOR FOR SELECT id,guid,PARENT_GUID FROM tb_tmp ;
DECLARE CONTINUE HANDLER FOR NOT FOUND SET nowID = NULL; -- 声明临时表,并获取数据--------------------------------------------------------------------
-- 定义临时表 tb_tmp(自增主键,标题,拓展信息,原表主键ID)
DROP TEMPORARY TABLE IF EXISTS tb_tmp; CREATE TEMPORARY TABLE tb_tmp (
id INT AUTO_INCREMENT PRIMARY KEY,
funcsOrder BIGINT,
ITEM_NO VARCHAR(200),
GUID BIGINT,
NAME VARCHAR(100) NULL,
ITEM_NO_INDEX BIGINT NULL,
PLAN_GUID BIGINT NULL,
PARENT_GUID BIGINT
); #所有数据
INSERT INTO tb_tmp( funcsOrder,ITEM_NO,GUID,NAME,ITEM_NO_INDEX,PLAN_GUID,PARENT_GUID)
SELECT CASE WHEN (
CASE WHEN INSTR(item_No, '.')>0
THEN CAST( SUBSTRING(item_No,(LENGTH(item_No)-INSTR(REVERSE(item_No), '.')+2)) AS SIGNED)
ELSE CAST(item_No AS SIGNED)
END )=0
THEN 2147483647
ELSE
CASE WHEN INSTR(item_No, '.')>0
THEN CAST( SUBSTRING(item_No,(LENGTH(item_No)-INSTR(REVERSE(item_No), '.')+2)) AS SIGNED)
ELSE CAST(item_No AS SIGNED)
END
END AS funcsOrder,item_no,guid, NAME,ITEM_NO_INDEX ,PLAN_GUID,PARENT_GUID
FROM sn93_elggtw_goal
WHERE PLAN_GUID=input_planGuid
ORDER BY PARENT_GUID,
(CASE WHEN (
CASE WHEN INSTR(item_No, '.')>0
THEN CAST( SUBSTRING(item_No,(LENGTH(item_No)-INSTR(REVERSE(item_No), '.')+2)) AS SIGNED)
ELSE CAST(item_No AS SIGNED)
END )=0
THEN 2147483647
ELSE
CASE WHEN INSTR(item_No, '.')>0
THEN CAST( SUBSTRING(item_No,(LENGTH(item_No)-INSTR(REVERSE(item_No), '.')+2)) AS SIGNED)
ELSE CAST(item_No AS SIGNED)
END
END ),item_no,guid; -- 临时表完毕------------------------------------------------------------------------------- -- 开游标
OPEN cur1;
/*游标向下走一步*/
FETCH cur1 INTO nowID,nowGuid,parentGuid; /* 循环体 */
WHILE ( nowID IS NOT NULL)
DO
-- 如果nowID=1,则表示第一行.设置item_no_index=1即可
IF nowID=1 THEN
SET newIndex=1;
ELSE
-- 如果不是第一行:
-- 再根据本行与上一行的数据进行判断:
-- A:本行父级id<>上一行的父级id,则本行为第一个子.设置index=1;
IF parentGuid!=preParentGuid THEN
SET newIndex=1;
ELSE
-- B:本行父级id==上一行的父级id,则本行为上一行的兄弟,设置index=上行index+1;
SET newIndex= preIndex + 1;
END IF;
END IF;
-- 更新index
UPDATE tb_tmp SET ITEM_NO_INDEX = newIndex WHERE id=nowID;
-- 更新上一行变量.
SET preIndex=newIndex;
SET preParentGuid=parentGuid; /*游标向下走一步*/
FETCH cur1 INTO nowID,nowGuid,parentGuid;
END WHILE; CLOSE cur1;
-- 游标处理临时表完毕---------------------------------------------------------------------
-- 根据临时表数据,更新真实表数据---------------------------------------------------------- update sn93_elggtw_goal inner join (sn93_elggtw_goal T1 INNER JOIN tb_tmp T2 ON T1.guid=T2.guid and T1.guid=T2.guid ) on T1.PLAN_GUID=input_planGuid
SET T1.ITEM_NO_INDEX=T2.ITEM_NO_INDEX ; -- 删除临时表
DROP TEMPORARY TABLE IF EXISTS tb_tmp;
-- over ----------------------------------------------------------------------------------
END// DELIMITER ;