The relational-to-object-oriented cross-model accessing capability in a multi-model and multi-lingual database system

Conventional database management systems (DBMS) are stand-alone, each supporting a single data model and corresponding data language (ML). One organization might operate several stand-alone DBMS independently, each of which requires the knowledge of a different ML to operate. The multi-model and multi- lingual database system offers a different approach. This system supports multiple MLs in a single database system. Thus, a relational database user of the multi-model and multi-lingual database system can create and manipulate a database according to the relational model and the SQL data language. On the same system, a hierarchical user can create and manipulate a database according to the hierarchical model and DL/I data language, and so on. Besides supporting many different models and languages on a single system, the multi-model and multi-lingual database system also allows the user to access a database created according to one ML as if it were created according to another. Thus, a relational user could manipulate a hierarchical database as if it is relational, i.e., the user would use a relational schema and SQL commands to manipulate a hierarchical database. The Cross-model accessing capability, Database design, Database implementation, Database management systems, base-model and base- language (i.e., hierarchical and DL/1) are invisible to the user. This additional capability is termed the cross-model accessing capability At this time the multi-model and multi-lingual database system supports the following MLs: relational and SQL, hierarchical and DL/I, network and CODASYL-DML, and object-oriented and the object-oriented data language. The system also supports a relational-to-hierarchical cross-model accessing capability.