在SQL Server中动态选择TOP @var

我怎么能有一个动态变量设置行量返回SQL Server?以下语法在SQL Server 2005+中无效:

DECLARE @count int
SET @count = 20

SELECT TOP @count * FROM SomeTable

当前回答

SELECT TOP (@count) * FROM SomeTable

这只适用于SQL 2005+

其他回答

declare @rows int = 10

select top (@rows) *
from Employees
order by 1 desc -- optional to get the last records using the first column of the table

在x0n的例子中，它应该是:

SET ROWCOUNT @top

SELECT * from sometable

SET ROWCOUNT 0

http://msdn.microsoft.com/en-us/library/ms188774.aspx

或者把变量放在括号里

DECLARE @top INT = 10;

SELECT TOP (@Top) *
FROM <table_name>;

SELECT TOP (@count) * FROM SomeTable

这只适用于SQL 2005+

也可以使用动态SQL并使用exec命令执行:

declare @sql  nvarchar(200), @count int
set @count = 10
set @sql = N'select top ' + cast(@count as nvarchar(4)) + ' * from table'
exec (@sql)

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