Help me about dyanmic SQL

create procedure [dbo].[select_column](@tablename varchar(20),@columnname varchar(20))as
  begin
     select @columnname from @tablename
  end

Msg 1087, Level 15, State 2, Procedure select_column, Line 3
Must declare the table variable "@tablename".

I have read some documents on internet and understand what is problem behind it.but not getting sample code to solve this error.Tell me how can I use table name dynamically.

thanks in advance.

View Complete Post