SQL server 两表联查及三表联查

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–合同表显示 跟用户表联查

–显示合同表所有信息
SELECT * FROM dbo.Contract
–合同表和用户表联查
SELECT h.Contract_id,h.Contract_Name,y.NetName,h.Contract_Money,h.Contract_Time,h.Contract_Enclosure FROM Contract h JOIN dbo.Users y on h.UsersID = y.ID
–第二种方法
SELECT * FROM USERS
SELECT h.Contract_id,h.Contract_Name,Y.ID,y.NetName,h.Contract_Money,h.Contract_Time,h.Contract_Enclosure
from Contract h , dbo.Users y where h.UsersID = y.ID

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–物品表 用户表 借用表 三表联查
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———–第一种方法
SELECT * froM dbo.Goods
Goods_ID
Select Top 4 h.Contract_id,h.Contract_Name,y.NetName,h.Contract_Money,h.Contract_Time,h.Contract_Enclosure From Contract h JOIN dbo.Users y on h.UsersID = y.ID where (Contract_id Not In (Select Top 0 Contract_id From Contract h JOIN dbo.Users y on h.UsersID = y.ID where Contract_Name like ‘%二号合同%’ Order by Contract_id asc)) And Contract_Name like ‘%二号合同%’ Order by Contract_id ASC
————第二种方法
SELECT b.Borrow_ID,g.Goods_Name,b.Borrow_Time,b.Borrow_Days,u.NetName,b.Borrow_Reason
,b.Borrow_State FROM dbo.Borrow b
JOIN dbo.Goods g ON b.Goods_Name=g.Goods_Name
JOIN dbo.Users u on b.UID=u.ID
———–第三种方法
SELECT b.Borrow_ID,g.Goods_Name,b.Borrow_Time,b.Borrow_Days,u.NetName,b.Borrow_Reason
,b.Borrow_State FROM dbo.Borrow b , dbo.Goods g , dbo.Users u where b.Goods_Name=g.Goods_Name and b.UID=u.ID

SELECT * FROM dbo.Borrow