Synopse Open Source

For instance, the following class definition will create an index for its SerialNumber property (up to 30 characters long if stored in an external database), and will expect a link to a model of diaper (TSQLDiaperModel) and the baby which used it (TSQLBaby).
An ID / RowID column will always be available (from TSQLRecord), so in this case, you would be able to make a fast look-up for a particular diaper from either its internal mORmot ID, or its official unique serial number:

/// table used for the Diaper queries
TSQLDiaper = class(TSQLRecord)
  private
    fSerialNumber: RawUTF8;
    fModel: TSQLDiaperModel;
    fBaby: TSQLBaby;
  published
    property SerialNumber: RawUTF8 index 30 read fSerialNumber write fSerialNumber
     stored AS_UNIQUE;
    property Model: TSQLDiaperModel read fModel write fModel;
    property Baby: TSQLBaby read fBaby write fBaby;
end;

Just a constant definition, and code sounds more readable.
It is worth saying that Delphi SOAP units uses a similar trick, by defining stored AS_ATTRIBUTE in its TRemotable classes.