当初学习SQL的时候掌握的不是很好,特别是一遇到长句就头晕,还请各路大侠帮我翻译下这两句SQL语句:SELECT G.*,[User].Username,(SELECT COUNT(*) FROM GroupUser WHERE GroupID=G.ID AND GroupID > 3) AS GroupUserCount FROM [Group] AS G INNER JOIN [User] ON G.UserID=[User].ID WHERE G.UserID=@UserID OR UserID=0
SELECT [User].*,[GroupUser].GroupID FROM [GroupUser] INNER JOIN [User] ON [User].ID=[GroupUser].UserID WHERE GroupID=@GroupID
感激不尽!!!
SELECT [User].*,[GroupUser].GroupID FROM [GroupUser] INNER JOIN [User] ON [User].ID=[GroupUser].UserID WHERE GroupID=@GroupID
感激不尽!!!
SELECT G.*,[User].Username,(SELECT COUNT(*) FROM GroupUser WHERE GroupID=G.ID AND GroupID > 3) AS GroupUserCount
FROM [Group] AS G
INNER JOIN [User] ON G.UserID=[User].ID
WHERE G.UserID=@UserID OR UserID=0
--先是Group表和User表关联查询,条件是G.UserID=[User].ID;
--然后select语句中包含了子查询,这个子查询的每个G.ID要与GroupUser的GroupID比较并且GroupID>3SELECT [User].*,[GroupUser].GroupID
FROM [GroupUser]
INNER JOIN [User] ON [User].ID=[GroupUser].UserID
WHERE GroupID=@GroupID
--内部连接表GroupUser和表User,条件是[User].ID=[GroupUser].UserID
"SELECT COUNT(*) FROM GroupUser WHERE GroupID=G.ID AND GroupID > 3"
返回的是个数值吧,这放在句中有什么意义?
(5) SELECT G.*,[User].Username,(SELECT COUNT(*) FROM GroupUser WHERE GroupID=G.ID AND GroupID > 3) AS GroupUserCount
(1) FROM [Group] AS G
(3) INNER JOIN [User]
(2) ON G.UserID=[User].ID
(4) WHERE G.UserID=@UserID OR UserID=0 (5)SELECT [User].*,[GroupUser].GroupID
(1)FROM [GroupUser]
(3)INNER JOIN [User]
(2)ON [User].ID=[GroupUser].UserID
(4)WHERE GroupID=@GroupID