🚀 go-pugleaf

Are there any preformance issues (good or bad) regarding the boxing and 
unboxing of class type objects?

Are the following code segement a succesful passing and returning of a ds 
refrence and not its value?

Please comment on the following code:
The mission is to fill a Dataset in DAL by using a DataSet object 
instantiated by BLL assembly.
( i havn;t tested this code. it's in theory correct...i think)

BLL assembly:
public void addTestTable()
{
    //NOTE: the DataSet ds has a table already defined during design time. 
an additional table (testTable) must be added to the
    //DataSet ds. For preformance optimization I want to use the refrence of 
the exiting DataSet ds and not a copy thereof.
    //How feasible is this approach? Is it worth the hype? And will this 
work?

    DAL.FillWithData( "SELECT * FROM testTable" ,  (object)ds 
,"myTestTable");

    if (ds.Tables["myTestTable"] != null) MessageBox.Show("Refrencing 
Success");

}


DAL assmebly:
public void FillWithData(string _sql, object _datasource, string _tablename)
{
        //assuming all connections are made and commandtext set.

        DataSet ds = (DataSet)_datasource;

        mysqlAdapter.Fill(ds, _tablename);

}