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7.3 Allowed Fields

In some cases we know the set of fields that may appear in the records of a given type, even if they are not mandatory. The %allowed special field is used to specify this restriction. The usage is:

     %allowed: field1 field2 ... fieldN

The field names are separated by one or more blank chracters.

If there are more or one %allowed fields in a record descriptor, all fields of all the records in the record set must be in the union of %allowed, %mandatory and %key. Otherwise an integrity error is raised.

Several %allowed fields can appear in the same record descriptor. The set of allowed fields is the union of all the entries.