set @chaoshiorg_uid=( SELECT max(pre_ucenter_members.uid) from pre_ucenter_members);
or
SELECT max(pre_ucenter_members.uid) into @chaoshiorg_uid from pre_ucenter_members;
or
SELECT max(pre_ucenter_members.uid) into @chaoshiorg_uid from pre_ucenter_members;
改成SELECT max(pre_ucenter_members.uid) into @chaoshiorg_uid from pre_ucenter_members;