I am writing a stored-procedure. But the table name is dynamic in this procedure. I want to get row number from my variable table. But where will I set @rownumber with return of select query?
Create Proc update_eMail (@tablename nvarchar(50), @columnname nvarchar(50)) AS Begin Declare @q_getrowNumber NVARCHAR(MAX) Declare @rownumber int SELECT @rownumber = Count(ID) FROM quotename(@tablename) // doesnt work END Thanks in advance
Here is one way to achieve the goal using dynamic sql
declare @sql NVARCHAR(4000)= '' set @sql = 'SELECT @rownumber = Count(ID) FROM '+ quotename(@tablename) exec sp_executesql @sql, N'@rownumber int output',@rownumber output 
You write wrong Procedure for dynamic query Try This. It will Work.
ALTER PROC update_eMail(@tablename NVARCHAR(50)) AS BEGIN DECLARE @RowNumber NVARCHAR(MAX)='' set @RowNumber='select Count(ID) FROM '+@tablename+'' exec(@RowNumber) END OR Try below Code in your Query
ALTER PROC update_eMail1 ( @tablename NVARCHAR(50) ) AS BEGIN DECLARE @sql NVARCHAR(4000)= '',@rownumber INT SET @sql = 'SELECT @rownumber = Count(ID) FROM '+quotename(@tablename) EXEC sp_executesql @sql, N'@rownumber int output',@rownumber OUTPUT SELECT @rownumber END 
This one will be easiest for you:
Create Proc update_eMail @tablename nvarchar(50) AS Begin EXEC ( 'SELECT Count(ID) FROM '+@tablename+'') END 