Updating local database with records received from webservice.

I'm stuck and hope someone can help me...

I'm trying to update records in a local database with records received via an xml webservice. The database schema's match, and the code below doesn't give me any errors. It just doesn't update.

Code:

---

Dim reader As New IO.StringReader(myxml)
Dim myxmlschema As String = myObject.PlanningGetSchema
Dim schemareader As New IO.StringReader(myxmlschema)
Dim ds As New DataSet
ds.ReadXmlSchema(schemareader)
ds.ReadXml(reader)

Dim adapter As New OdbcDataAdapter("Select * From Planning", dbconn)
Dim cb As New OdbcCommandBuilder(adapter)
Dim ds2 As New DataSet()
adapter.Fill(ds2)

Dim table As DataTable = ds.Tables(0)
table.TableName = "Table"
table.AcceptChanges()
For Each row As DataRow In table.Rows()
  row.SetModified()
Next

ds2.Merge(table)
ds2.AcceptChanges()

---

Any idea what i'm doing wrong ?

[edit]
some extra info . the data i receive is coming from an mssql2000 server. I'm trying to update a local mysql 5 database, but also tried it with sqlexpress 2005. I'm working in vs2005, but coulnd't get it to work in 2003 either..
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