An extension of SQL to capture more information from objects with many-many relationship

Many decision support applications such as task assignment, truck deliveries, airline crew scheduling problems usually need to get information from objects with many-many relationship. However, with current relational operators including the complete set of relational algebra it is difficult to get required information from objects with a many-many relationship. We extend SQL so that users can capture more information from objects with a many-many relationship by using the query language directly. The relational operators were extended with six operators, namely, match, maxmatch, cover, mincover, partition, and minpartition.<>