Model 204 is an on-line and batch DBMS built on a proprietary inverted file access method. The system includes an integrated data dictionary for flexibility in defining and protecting data acquisition. An inverted file, relational system, like Model 204, can support applications that require very large data bases, high transaction volumes, and a large number of concurrent users--all with a high degree of flexibility and efficiency. In that respect, it differs significantly from the standard relational DBMSs that are notoriously slower and more cumbersome to manipulate.
The Model 204 system is fully integrated, with its own query language and communications interfaces to CICS, CMS, and Thorn EMI's Shadow II. It comes with its own 4GL and can support most popular third-generation languages.
Model 204 can also be configured in a mainframe-microcomputer environment with its PC/Workshop product. It also supports a LAN environment.
Currently, DAL supports neither Model 204 or IMS database. There is no plan in the near future for supporting these two products.