The EDM provides the means both for various readings of the lexical items to be expanded, and for some of the different readings to be queries to be ruled-out if they break typing restrictions provided in the database model.
The EDM definition resides in two files. The first is a model of the database containing specifications of:
Some of this information is used to rule-out interpretations of the query that do not make sense in the domain.
The second file provides a mapping between expressions in First Order Logic and the Untyped Relational Calculus.
In addition to allowing the translation process, this mapping gives the possibility of expanding various lexical ambiquities.