MYSQL存储过程，实在无法，求解释？？ - MySQL社区

BEGIN
declare Pmax int; -- 记录表中最大ID
declare Pmin int; -- 记录表中最小ID
declare PID smallint(6);-- 记录当前统计Pack_ID，用于与总表userservicerelation联系，统计Pack_ID的人气
delete from packcollectionrank;-- 清空表
insert into packcollectionrank(Pack_ID) select distinct Pack_ID from products ;-- 插入所有Pack_ID到统计表packcollectionrank
select MAX(ID) into Pmax from packcollectionrank;
select MIN(ID) into Pmin from packcollectionrank;
while Pmin<=Pmax do-- 插入所有Pack_ID的人气，没订阅默认为0
select Pack_ID into PID from tdxtb_packcollectionrank where ID=Pmin;
set @sql1=CONCAT("UPDATE packcollectionrank SET Collection_count=(SELECT COUNT(*) FROM userservicerelation WHERE Pack_ID=",PID," AND Relation_Status=6) WHERE Pack_ID=",PID,";");
PREPARE rankpack1 FROM @sql1;
EXECUTE rankpack1;
set Pmin=Pmin+1;
end while;
-- 插入
END

复制代码