ODP OracleCommandBuilder. Updating a table including DATE columns.

Question

Hi
I have a problem with the OracleCommandBuilder not creating the correct update commands when I have DATE type columns in the table.
I have created a test table (called DATETEST) with three columns:
STRINGCOLUMN     VARCHAR2 10
DATECOLUMN DATE
NUMBERCOLUMN     NUMBER
The STRINGCOLUMN is the primary key.
Then I created a typed dataset that looks like this:
STRINGCOLUMN     string
DATECOLUMN string
NUMBERCOLUMN     long
This is the XML schema for the typed dataset:
<?xml version="1.0" encoding="utf-8" ?>
<xs:schema id="DateDS" targetNamespace="http://tempuri.org/DateDS.xsd" elementFormDefault="qualified" attributeFormDefault="qualified" xmlns="http://tempuri.org/DateDS.xsd" xmlns:mstns="http://tempuri.org/DateDS.xsd" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:msdata="urn:schemas-microsoft-com:xml-msdata">
     <xs:element name="DateDS" msdata:IsDataSet="true">
          <xs:complexType>
               <xs:choice maxOccurs="unbounded">
                    <xs:element name="DATETEST">
                         <xs:complexType>
                              <xs:sequence>
                                   <xs:element name="DATECOLUMN" type="xs:string" minOccurs="0" />
                                   <xs:element name="STRINGCOLUMN" type="xs:string" minOccurs="0" />
                                   <xs:element name="NUMBERCOLUMN" type="xs:long" minOccurs="0" />
                              </xs:sequence>
                         </xs:complexType>
                    </xs:element>
               </xs:choice>
          </xs:complexType>
     </xs:element>
</xs:schema>
And this is the test code:
Dim connection As Oracle.DataAccess.Client.OracleConnection
Dim adapter As New Oracle.DataAccess.Client.OracleDataAdapter()
Dim dbCommand As New Oracle.DataAccess.Client.OracleCommand()
Dim sqlstring As String
Dim data As New DateDS() 'Typed dataset
Const ConnectionString As String = "User Id=............."
Try
'Connect to database
connection = New OracleConnection(ConnectionString)
connection.Open()
'Get data from table DATETEST
dbCommand.CommandText = "SELECT STRINGCOLUMN, TO_CHAR(DATECOLUMN) AS DATECOLUMN, NUMBERCOLUMN FROM DATETEST"
dbCommand.Connection = connection
adapter.SelectCommand = dbCommand
adapter.Fill(data, "DATETEST")
'Make changes to dataset
data.DATETEST(0).DATECOLUMN = Now()
data.DATETEST(0).NUMBERCOLUMN = data.DATETEST(0).NUMBERCOLUMN + 1
'Update database
sqlstring = "SELECT * FROM DATETEST"
adapter.SelectCommand = New OracleCommand(sqlstring, connection)
Dim custCB As New Oracle.DataAccess.Client.OracleCommandBuilder()
custCB.DataAdapter = adapter
adapter.Update(data, "DATETEST")
'Disconnect
connection.Close()
connection.Dispose()
Catch exc As Exception
MessageBox.Show(exc.Message)
End Try
Getting the data from the database is not a problem.
The dataset contains the correct information.
But updating the database is impossible.
I get errors like:
ORA-01861: literal does not match format string
And if I don't specify a DATE format in the TO_CHAR statement I get this error:
Concurrency violation: the UpdateCommand affected 0 records.
I think I've tried everything.
I've used the OracleGlobalization class, with the SetSessionInfo method.
I've tried all different types of date conversions to make sure that
the date format on the database is the same as in the dataset.
I've tried to change the NLS parameters on the DB server and in the registry on the client.
I've tried to change the DATECOLUMN type in the typed dataset from string to Oracle.DataAccess.Types.OracleDate
But it still doesn't work.
The default date format on the DB 9i server is AMERICAN,(DD-MON-RR).
A strange thing is that when I instead of using the ODP classes use
the System.Data.OracleClient and its OracleCommandBuilder
the code works perfectly without any errors.
This is the test code that works:
Dim connection As System.Data.OracleClient.OracleConnection
Dim adapter As New System.Data.OracleClient.OracleDataAdapter()
Dim dbCommand As New System.Data.OracleClient.OracleCommand()
Dim data As New DateDS()
Dim sqlstring As String
Const ConnectionString As String = "User Id=......."
Try
'Connect to database
connection = New System.Data.OracleClient.OracleConnection(ConnectionString)
connection.Open()
'Get data from table DATETEST
dbCommand.CommandText = "SELECT STRINGCOLUMN, TO_CHAR(DATECOLUMN,'YYYY-MM-DD HH24:MI:SS') AS DATECOLUMN, NUMBERCOLUMN FROM DATETEST"
dbCommand.Connection = connection
adapter.SelectCommand = dbCommand
adapter.Fill(data, "DATETEST")
'Make changes to dataset
data.DATETEST(0).DATECOLUMN = Now()
data.DATETEST(0).NUMBERCOLUMN = data.DATETEST(0).NUMBERCOLUMN + 1
'Update database
sqlstring = "SELECT * FROM DATETEST"
adapter.SelectCommand = New System.Data.OracleClient.OracleCommand(sqlstring, connection)
Dim custCB As New System.Data.OracleClient.OracleCommandBuilder()
custCB.DataAdapter = adapter
adapter.Update(data, "DATETEST")
'Disconnect
connection.Close()
connection.Dispose()
Catch exc As Exception
MessageBox.Show(exc.Message)
End Try
My experience until this came up is that the ODP provider is better on everything
than the microsoft Oracle provider so I don't want to switch unless I have to.
Could someone that have used the ODP OracleCommandBuilder for updating a table including DATE columns with a typed dataset please give me some tips on how to make this work?
I would be the happiest man on earth if someone had a solution :-)
Erik

Answer 1

Don't convert the dates to strings. Ever.
The command builder uses the metadata returned from the select command to build the insert/update commands. Using to_char in the query tells ODP that that is a varchar2 column. If you omit the to_char the commandBuilder will know to bind a date parameter in that spot.
Also in your typed dataset you should change the type from a string to a date.
David