Deletion of data from child tables with multiple parents Grant US-7801921-B2 United States of America 21 Sep 2010
System and method for managing a hierarchy of databases Grant US-7487171-B2 United States of America 03 Feb 2009
Method and system for intra-table referential integrity for relational database systems Grant US-7257587-B2 United States of America 14 Aug 2007