SQL Server— 子查询

实例应用

举例：关羽的银行卡号为”6225547858741263″，查询出余额比关羽多的银行卡信息，显示卡号，身份证，姓名，余额。

方法一：设置变量值

declare @balance money
select @balance = (select CardMonev from BankCard where CardNo='6225547858741263')
select CardNo 卡号,AccountCode 身份证,RealName 姓名,CardMoney 余额 from BankCard
inner join AccountInfo on BankCard.AccountId = AccountInfo.AccountId
where CardMoney > @balance

方法二：使用子查询

select CardNo 卡号,AccountCode 身份证,RealName 姓名,CardMoney 余额 from BankCard
inner join AccountInfo on BankCard.AccountId = AccountInfo.AccountId
where CardMoney > (select CardMonev from BankCard where CardNo='6225547858741263')