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MYSQL存储过程中使用游标嵌套的实例 MySQL 存储过程 delimiter $$drop procedure if exists findErrorLifeRoute $$CREATE PROCEDURE findErrorLifeRoute() BEGINdeclare routeId,routeStopId BIGINT ; declare str,tmp_street VARCHAR(255) ; DECLARE l_done

MYSQL存储过程中使用游标嵌套的实例

MySQL 存储过程
delimiter $$
drop procedure if exists findErrorLifeRoute $$
CREATE PROCEDURE findErrorLifeRoute()   
BEGIN
declare routeId,routeStopId BIGINT   ; 
declare str,tmp_street VARCHAR(255)  ; 
DECLARE l_done,num,life,localId,tmp_localId INT DEFAULT  0;
-- 声明两个游标,第二个游标使用到第一个的查询结果
DECLARE grade_csr cursor  FOR SELECT route_id FROM routes where   LIFE_CYCLE_STATUS<39998 and LIFE_CYCLE_STATUS>35001;
DECLARE class_csr cursor  FOR SELECT LOCATION_INNER_ID,STREET FROM route_stops  WHERE ROUTE_ID=routeId order by STOP_NUMBER asc;
DECLARE CONTINUE HANDLER FOR NOT FOUND SET l_done=1;
  OPEN grade_csr;
-- 第一个循环
  grade_loop: LOOP   -- Loop through org_grade
    FETCH grade_csr into routeId;
    IF l_done=1 THEN
       LEAVE grade_loop;
    END IF;
		SET num=0;
		set tmp_street=null;
		set tmp_localId=0;
    OPEN class_csr;
-- 第二个循环
    class_loop: LOOP      -- Loop through class in grade.
      FETCH class_csr INTO localId,str;
      IF l_done=1 THEN
         LEAVE class_loop;
      END IF; 
     if localId =tmp_localId or (str is not null and str=tmp_street) THEN
				set tmp_street=str;
				set tmp_localId=localId;
			else
				set num=num+1;
				set tmp_street=str;
				set tmp_localId=localId;
		end if;		 
-- 结束第一个循环
    END LOOP class_loop;
    CLOSE class_csr;
    SET l_done=0;
		set life=36000+(num-1)*100+6; 
		INSERT into route_tmp (select ROUTE_ID,LIFE_CYCLE_STATUS,num,life,ACCOUNT_ID,str from routes r where r.ROUTE_ID=routeId and LIFE_CYCLE_STATUS=life  );
-- 结束第二个循环
  END LOOP grade_loop;
  CLOSE grade_csr;
END $$
delimiter ;
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