Parent Columns and Child Columns don't have type-matching columns.

English:
Today I got an exception with the following message and stack trace when deserializing a DataSet.

Parent Columns and Child Columns don't have type-matching columns.
   at System.Data.DataRelation.CheckState()
   at System.Data.DataRelation.Create(String relationName, DataColumn[] parentColumns, DataColumn[] childColumns, Boolean createConstraints)
   at System.Data.DataRelation..ctor(String relationName, DataColumn[] parentColumns, DataColumn[] childColumns)
   at System.Data.XSDSchema.HandleKeyref(XmlSchemaKeyref keyref)
   at System.Data.XSDSchema.HandleDataSet(XmlSchemaElement node, Boolean isNewDataSet)
   at System.Data.XSDSchema.LoadSchema(XmlSchemaSet schemaSet, DataSet ds)
   at System.Data.DataSet.ReadXml(XmlReader reader, XmlReadMode mode, Boolean denyResolving)
   at System.Data.DataSet.ReadXmlSerializable(XmlReader reader)
   at System.Data.DataSet.System.Xml.Serialization.IXmlSerializable.ReadXml(XmlReader reader)
   at System.Xml.Serialization.XmlSerializationReader.ReadSerializable(IXmlSerializable serializable, Boolean wrappedAny)
   at Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationReaderOrionWS.Read35_ServerActionResponse()
   at Microsoft.Xml.Serialization.GeneratedAssembly.ArrayOfObjectSerializer64.Deserialize(XmlSerializationReader reader)
   at System.Xml.Serialization.XmlSerializer.Deserialize(XmlReader xmlReader, String encodingStyle, XmlDeserializationEvents events)


However, the columns did have the same data type. It took me ages to find out that they need to have the same DateTimeMode as well.

Deutsch:
Ich habe obige Exception und Stacktrace erhalten beim Deserialisieren eines DataSet.

Dabei hatten die Spalten den selben Datentyp. Es hat ewig gedauert herauszufinden, dass die Spalten auch den gleichen DateTimeMode haben müsen.