近日做项目中需要在EXEC执行Sql字符串时动态的传入参数并接收返回值,于是研究了一下SqlServer中sp_executesql的使用方法,并做了如下的例子。
在使用sp_executesql动态传入与接收返回参数时需注意以下事项,以避免大家走弯路。例子中@SQLString,@ParmDefinition一定要使用NVARCHAR类型,否则会报“过程需要参数 '××××' 为 'ntext/nchar/nvarchar' 类型。”错误。文档中说这两个变量赋值的字符串前要加N,我试了试,没加也不报错,不过你最好加上。毕竟人家是官方文档么。--传递一个Int类型参数
DECLARE @IntVariable INTDECLARE @SQLString NVARCHAR(500)DECLARE @ParmDefinition NVARCHAR(500)SET @SQLString = N'SELECT * FROM pubs.dbo.employee WHERE job_lvl = @level'SET @ParmDefinition = N'@level tinyint'SET @IntVariable = 35EXECUTE sp_executesql @SQLString, @ParmDefinition,@level = @IntVariable--SET @IntVariable = 32--EXECUTE sp_executesql @SQLString, @ParmDefinition,@level = @IntVariable---------------------------------------------------------------------------------传递一个varchar类型参数DECLARE @VarVariable varchar(500)DECLARE @SQLString NVARCHAR(500)DECLARE @ParmDefinition NVARCHAR(500)SET @SQLString = N'SELECT * FROM pubs.dbo.employee WHERE fname = @VarVariable'SET @ParmDefinition = N'@VarVariable varchar(500)'SET @VarVariable = 'Helen'EXECUTE sp_executesql @SQLString, @ParmDefinition,@VarVariable---------------------------------------------------------------------------------传递两个参数,一个varchar类型参数接收返回值,一个Int类型参数DECLARE @VarVariable VARCHAR(500)DECLARE @IntVariable INTDECLARE @SQLString NVARCHAR(500)DECLARE @ParmDefinition NVARCHAR(500)SET @SQLString = N'SELECT @VarVariable = Count(*) FROM pubs.dbo.employee WHERE job_lvl = @IntVariable'SET @IntVariable = 35SET @ParmDefinition = N'@VarVariable VARCHAR(500) OUT,@IntVariable INT'SET @VarVariable = 'Helen'EXECUTE sp_executesql @SQLString,@ParmDefinition,@VarVariable OUT,@IntVariableprint @VarVariable