fourth generation language


fourth generation language

(language)(4GL, or "report generator language") An"application specific" language, one with built-in knowledgeof an application domain, in the way that SQL has built-inknowledge of the relational database domain.

The term was invented by Jim Martin to refer tonon-procedural high level languages built arounddatabase systems.

Fourth generation languages are close to natural languageand were built with the concept that certain applicationscould be generalised by adding limited programming ability tothem.

When given a description of the data format and the report togenerate, a 4GL system produces COBOL (or other 3GL) code,that actually reads and processes the data and formats theresults.

Some examples of 4GL are: database query language e.g.SQL;Focus, Metafont, PostScript, S, IDL-PV, WAVE,Gauss, Mathematica, and data-stream languages such asAVS, APE, Iris Explorer.