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在SQL語(yǔ)句中，SQL條件語(yǔ)句無(wú)疑是使用最廣，最常見(jiàn)的SQL語(yǔ)句之一，下面就將為您介紹幾個(gè)使用SQL條件語(yǔ)句，供您學(xué)習(xí)參考。

----查詢(xún)StudentMarks 最大的前三條記錄

select  top 3 StudentID,StudentName,Mark from StudentMarks order by Mark desc

----查詢(xún)StudentMarks 的第30~40條記錄

1、從前30條的后面, 取前10條

select top 10 * from StudentMarks where StudentID not in(select top 30 StudentID from StudentMarks)

2、先正序取40條, 再反序取10條

select top 10* from (select top 40* from StudentMarks order by Mark ) a
order by Mark desc

3、、利用臨時(shí)表
select top 40 * into #Stm from StudentMarks order by Mark

select top * from #Stm  order by Mark desc

----查詢(xún)和London同屬于一個(gè)國(guó)家的城市的客戶(hù)
select distinct * from customers where country in
( select country from customers where city='London')

----查詢(xún)和London,Paris同屬于一個(gè)國(guó)家的城市的客戶(hù)
select * from customers where country in
(select country from Customers where City in ('London','Paris'))

----查詢(xún)單價(jià)大于Dofu的產(chǎn)品名
select ProductName from Products where UnitPrice>
(select UnitPrice from Products where ProductName='Tofu')