Other Names:



Programming Language + Databases




Rocket Software

Previous Vendors:

Computer Corporation of America


z/OS  z/VM  z/VSE  

Short Description:

Hierarchical database management system


Hierarchical, pre-relational database management system developed by Computer Corporation of America in 1972. Includes a programming language and application development environment with its own language called User Language. Applications use the M204 Remote Command Line (RCL) language to access databases.

Options available include:

  • VTAM Printer Support - allowing User Language programs to route output to VTAM printers
  • DB2 Support (UL/DB2) - allowing User Language to access DB2 databases using SQL
  • SQL access to Model 204 data. Remote programs can use SQL to access Model 204 data using the Connect for Model 204 software.
  • Parallel Query Option (Parallel Query Option/204, or PQO) - data sharing between multiple Model 204 subsystems.

Emulated by the free Windows/Linux based software Database Programmer's Toolkit.

Entry last updated: 07-Aug-2013

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