A relational database is disclosed which includes a number of target tables each exhibiting a different type, such as a general contact table, a personal contact table and a department contact table. The relational database includes a super-column which is divided into a number of columns corresponding to the number of types of target tables. A respective column is allocated in the super-column for each of the types of the target tables. Valuable system memory space is consequently conserved. Multiple-typed tables and multi-targeted tables are supported, and multi-version data storage capabilities are provided.