How to test if a DataSet is empty?

Question

I'm modifying someone else's code where a query is performed using the following:

DataSet ds = new DataSet();
SqlDataAdapter da = new SqlDataAdapter(sqlString, sqlConn);
da.Fill(ds);

How can I tell if the DataSet is empty (i.e. no results were returned)?

Answer 1

I would test if ds.Tables.Count = 0, because all a DataSet is is a collection of Tables with schema, right?

alternately, from the MSDN:

Return Value Type: System..::.Int32 The number of rows successfully added to or refreshed in the DataSet. This does not include rows affected by statements that do not return rows.

Answer 2

You don't have to test the dataset. The Fill() method returns the # of rows added. See MSDN

Answer 3

If I understand correctly, this should work for you

if (ds.Tables[0].Rows.Count == 0)
{
    //
}

Answer 4

You should loop through all tables and test if table.Rows.Count is 0

bool IsEmpty(DataSet dataSet)
{
    foreach(DataTable table in dataSet.Tables)
        if (table.Rows.Count != 0) return false;

    return true;
}