1 definition
for fourth generation language
From The Free On-line Dictionary of Computing (27 SEP 03) :
fourth generation language
(4GL) An "application specific" language, one with
built-in knowledge of an application domain, in the way that
SQL has built-in knowledge of the database domain. Pure
4GLs do not contain conditionals (if-then-else) and loops
(for, while, do), though some languages are combinations of
third generation languages and 4GLs.
The term was invented by Jim Martin to refer to
non-procedural high level languages built around
database systems. The first three generations were
developed fairly quickly, but it was still frustrating, slow,
and error prone to program computers, leading to the first
"programming crisis", in which the amount of work that might
be assigned to programmers greatly exceeded the amount of
programmer time available to do it. Meanwhile, a lot of
experience was gathered in certain areas, and it became clear
that certain applications could be generalised by adding
limited programming languages to them. Thus were born report
generator languages, which were fed a description of the data
format and the report to generate and turned that into a
COBOL (or other language) program which actually contained
the commands to read and process the data and place the
results on the page.
Some other successful 4th-generation languages are: database
query languages, e.g. SQL; Focus, Metafont,
PostScript, RPG-II, S, IDL-PV/WAVE, Gauss,
Mathematica; and data-stream languages such as AVS,
APE, Iris Explorer.
(2003-07-29)
