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    MDSError

    Exception raised for errors when reading or writing an in-memory dataset.

      Declaration

      Source position: memds.pp line 54

      type

  MDSError = class(Exception)
  end;

      Inheritance

      Description

      MDSError is an Exception type raised when an error occurs while reading or writing values for an in-memory dataset. MDSError is raised in the TMemDataset.RaiseError method and uses messages defined in resource strings in the implementation for the unit, including:

      • Fieldtype of Field "%s" not supported
      • Bookmark %d not found
      • Error in data stream at position %d
      • Wrong data stream marker at position %d. Got %d, expected %d'
      • Filename must not be empty

      An MDSError exception will be raised when a field definition uses a data type not supported in TMemDataset. The exception will be raised for the following field types:

      • ftADT
      • ftCursor
      • ftDataSet
      • ftDBaseOle
      • ftFmtMemo
      • ftGraphic
      • ftIDispatch
      • ftInterface
      • ftOraBlob
      • ftOraClob
      • ftParadoxOle
      • ftReference
      • ftTimeStamp
      • ftTypedBinary
      • ftVariant
      • ftUnknown

      See also

      Name Description
      TMemDataset.FieldDefs Definitions of available fields in the underlying database.
      TField.DataType The data type of the field.