解决了它我就觉得你是高手

[Eric1006]

declare @firstfield varchar(20)
declare @first_pkid numeric(2)
declare @secondfield varchar(20)
declare @second_pkid numeric(2)
declare @totalcount int
/*以下几个变量可以在程序中定义，这里是暂时为它定义量值*/
select @firstfield='zn'
select @first_pkid='3'
select @secondfield='indeg'
select @second_pkid='21'
/*目的是满足@firstfield=convert(nvarchar,@first_pkid)的记录数目@totalcount，
不用exec sp_executesql @str的方法因为还要对记录数@totalcount进行操作*/
select @totalcount=count(distinct pkid) from table_yeikue where @firstfield=convert(nvarchar,@first_pkid) --这里不能通过
select @totalcount

各位，我该怎么改，或者有什么变通的方法？

[Eric1006]

多谢各位高手！！！

[pengdali]

declare @firstfield varchar(20)
declare @first_pkid numeric(2)
declare @secondfield varchar(20)
declare @second_pkid numeric(2)
declare @totalcount int

select @firstfield='zn'
select @first_pkid='3'
select @secondfield='indeg'
select @second_pkid='21'


declare @sql varchar(4000)
set @sql=N'select @totalcount=count(distinct pkid) from table_yeikue where '+@firstfield+'='+cast(@first_pkid as nvarchar(10))
exec sp_executesql @sql,N'@totalcount int output',@totalcount output


select @totalcount

[nboys]

不能用select直接返回值
select @totalcount=count(distinct pkid) from table_yeikue where @firstfield=convert(nvarchar,@first_pkid) --这里不能通过
select @totalcount

用sp_executesql

[txlicenhe]

...
declare @sql varchar(4000)
set @sql='select @totalcount=count(distinct pkid) from table_yeikue where '+@firstfield+'='+cast(@first_pkid as nvarchar(10))
+ ' select @totalcount '
exec(@sql)

我不是高手，也不想成为高手，只想学习。

[nboys]

declare @firstfield varchar(20)
declare @sql varchar(8000)
declare @first_pkid numeric(2)
declare @secondfield varchar(20)
declare @second_pkid numeric(2)
declare @totalcount int
select @firstfield='zn'
select @first_pkid='3'
select @secondfield='indeg'
select @second_pkid='21'

set @sql=N'select @totalcount=count(distinct pkid) from table_yeikue where '+@firstfield+'='+cast(@first_pkid as nvarchar(10))+''
exec sp_executesql @sql,N'@totalcount int output',@totalcount output

print @totalcount

[Eric1006]

pengdali(大力 V2.0)跟 nboys()的方法都存在：
过程需要参数 '@statement' 为 'ntext/nchar/nvarchar' 类型

[Eric1006]

txlicenhe(不做技术高手)：
declare @sql varchar(4000)
set @sql='select @totalcount=count(distinct pkid) from table_yeikue where '+@firstfield+'='+cast(@first_pkid as nvarchar(10))
+ ' select @totalcount ' ---这里存在未定义变量问题
exec(@sql)

[pengdali]

declare @firstfield varchar(20)
declare @first_pkid numeric(2)
declare @secondfield varchar(20)
declare @second_pkid numeric(2)
declare @totalcount int

select @firstfield='zn'
select @first_pkid='3'
select @secondfield='indeg'
select @second_pkid='21'


declare @sql nvarchar(4000)
set @sql=N'select @totalcount=count(distinct pkid) from table_yeikue where '+@firstfield+'='+cast(@first_pkid as nvarchar(10))
exec sp_executesql @sql,N'@totalcount int output',@totalcount output


select @totalcount

[txlicenhe]

declare @firstfield varchar(20)
declare @first_pkid numeric(2)
declare @secondfield varchar(20)
declare @second_pkid numeric(2)

/*以下几个变量可以在程序中定义，这里是暂时为它定义量值*/
select @firstfield='zn'
select @first_pkid='3'
select @secondfield='indeg'
select @second_pkid='21'


declare @sql varchar(4000)
set @sql=' declare @totalcount int select @totalcount=count(distinct pkid) from table_yeikue where '+@firstfield+'='+cast(@first_pkid as nvarchar(10))
+ ' select @totalcount ' ---这里存在未定义变量问题
exec(@sql)

[CrazyFor]

参考:

declare @tcnt int
declare @paras varchar(100)
DECLARE @SQLString NVARCHAR(500)
set @paras ='1,3,5'
set @sqlstring=N'select @cnt=count(*) from sysobjects where id in ('+@paras+')'

set @tcnt=0
execute sp_executesql
@sqlstring,
N'@cnt int output',
@cnt=@tcnt output
select @tcnt


select * from sysobjects



Create Procedure GetMaxID
@TableName varchar(100), @ID int output
as
begin
declare @sql nvarchar(1000)
set @sql='select @ID = count(ID) from '+@TableName
exec sp_executesql @sql,N'@id int output',@id output
end