A method and system for generating a database query language request for performing a join between a plurality of database tables including a first database table and a second database table. The first table includes a first plurality of fields and the second database table includes a second plurality of fields, where each one of the plurality of fields has a particular meaning. The method and system includes providing a plurality of expressions that communicate the meaning of the each of the fields in the first and second plurality of fields. A user then submits a query requesting information from the tables in the form of a conjunction of literals. Each of the literals are then mapped to all matching expressions to provide a list of fields to be queried. The list of fields includes a first field from the first table and a second field from the second table, such that the mapping indicates that the first and second fields have the same meaning. After mapping the literals to the expressions, the database query language request is generated using the list of fields, such that the database query language request includes a join between the first and second fields. The first and second tables are then queried using the database query language request to provide the requested information.