Question

sql count()，sum()错误

SELECT COUNT(a.F_UserID)FROM [ActiveDB]..T_GamingUserHistoryInfo aSELECT SUM(b.F_GamingNum)FROM [ActiveDB]..T_GamingUserInfo b
SELECT COUNT(A.F_UserID),SUM(F_GamingNum) --琉璃卡总数FROM [ActiveDB]..T_GamingUserHistoryInfo A, [ActiveDB]..T_GamingUserInfo B
结果为什么是这样：

Answer 1

SELECT 这里应该有一个关联字段,COUNT(a.F_UserID) as 总数1
FROM [ActiveDB]..T_GamingUserHistoryInfo aSELECT 这里应该有一个关联字段,SUM(b.F_GamingNum) as 总数2FROM [ActiveDB]..T_GamingUserInfo b
两张表联合查询，应该有关联字段才行
select A.总数1,B.总数2from (SELECT 这里应该有一个关联字段,COUNT(a.F_UserID) as 总数1FROM [ActiveDB]..T_GamingUserHistoryInfo a) A,(SELECT 这里应该有一个关联字段,SUM(b.F_GamingNum) as 总数2FROM [ActiveDB]..T_GamingUserInfo b) bwhere A.字段=B.字段