However recfix checks more than the syntactical integrity of the recfile. It also checks certain semantics and that the data is self-consistent. To do this, it uses the special fields of the record, some of which were introduced above (see Constraints on Record Sets). It is a good idea to use the special fields to stipulate the “enterprise rules” of the data.
Errors will be reported if any of the following special keywords are present and the data does not match the stipulated conditions
%mandatory
%prohibit
%unique
%key
%typedef and %type
%size
%constraint
%confidential