如何判断字符串表示的布尔型变量是否为真

[dlss]

如何判断字符串表示的布尔型变量是否为真呢？
例如
declare @str nvarchar(1024)
set @str= '5=5 and 6=6'

如何判断@str是真是假呢？

[Limpire]

declare @str nvarchar(1024)
set @str = '5=5 and 6=6'
declare @SQL nvarchar(4000),@True bit
set @SQL = 'if (' + @str + ') set @True = 1 else set @True = 0'
exec sp_executesql @SQL, N'@True bit output', @True output
select @True

[-狙击手-]

declare @str varchar(1024)
set @str = ' 5=5 '
declare @SQL varchar(4000)
set @SQL = 'select 1 where (' + @str + ')'
exec(@sql)
if @@rowcount > 0  
  print 'true'
else 
  print 'false'


true
            


set @str = '5=5 and 6>6'
set @SQL = 'select 1 where ' + @str 
exec(@sql)
if @@rowcount > 0  
  print 'true'
else 
  print 'false'

----------- 

false

[-狙击手-]

declare @str varchar(1024)
set @str = ' 5=5 and 6 =6 '
declare @SQL varchar(4000)
set @SQL = 'select 1 where (' + @str + ')'
exec(@sql)
if @@rowcount > 0  
  print 'true'
else 
  print 'false'
/*

true

*/

[zefuzhang2008]

楼上正解