OracleDataAdapter.Fill() causes System.OverflowException on certain numbers

Question

This test shows how a value calculated in the database and stored in a column of type "number" (default scale/precision) causes an error upon retrieval using the OradleDataAdapter.Fill() method. The data type of the receiving column is irrelevant. The following example uses a decimal, but double, float, int, etc... all cause the same System.OverflowException error.
Does anyone have a good suggestion of how to best handle this problem?
I am using ODP.NET 9.2.0.4.0 (OraWin9204.exe) with Oracle9i (9.2.0.4.0) running both client and server on Windows 2000, using Visual Studio 2003.
<code>
/// <summary>
/// The following test illustrates how a value that was calculated in the database
/// causes an overflow error when retreiving it using the Oracle.DataAccess.Client
/// </summary>
public void ODP_CalculatedNumberIntoDecimalOverflowError()
     using (OracleConnection conn = new OracleConnection(CONNECT_STRING))
          conn.Open();
          try
               using (IDbCommand createCmd = conn.CreateCommand())
                    createCmd.CommandText = "create table overflow_test (num number)";
                    createCmd.ExecuteNonQuery();
               using (IDbCommand insertCmd = conn.CreateCommand())
                    insertCmd.CommandText = "insert into overflow_test (num) values (61 / 3)";
                    insertCmd.ExecuteNonQuery();
               using (OracleCommand selectCmd = conn.CreateCommand())
                    selectCmd.CommandText = "select * from overflow_test";
                    DataTable overflowTest = new DataTable("overflow_test");
                    DataColumn num = new DataColumn("num", typeof (decimal));
                    overflowTest.Columns.Add(num);
                    OracleDataAdapter oda = new OracleDataAdapter(selectCmd);
                    oda.Fill(overflowTest);
                    int i = 0;
                    foreach (DataRow row in table.Rows)
                         Console.Out.Write("Row[{0}]:", i);
                         for (int j = 0; j < row.Table.Columns.Count; j++)
                              Console.Out.Write(" {0}", row[j]);
                         Console.Out.WriteLine();
                         i++;
          finally
               using (IDbCommand deleteCmd = conn.CreateCommand())
                    deleteCmd.CommandText = "drop table overflow_test";
                    deleteCmd.ExecuteNonQuery();
</code>

Answer 1

The problem is even worse: it also happens with aggregate functions like AVG
CREATE Table Test (
Value NUMBER(10,0)
INSERT INTO Test VALUES (20);
INSERT INTO Test VALUES (20);
INSERT INTO Test VALUES (21)
SELECT AVG(Value) from Test
Adding the SafeMapping means we have to adjust our code to expect string values instead of decimals
The other workaround: (use ROUND or TRUNC) means we have to adjust all Sql statements!
Please solve this bug in the ODP.NET client, i.e. create a way to get normal .NET native type values into a DataSet. (oda.TruncateDecimals = true?)