fourth-generation language


fourth-generation language

[′fȯrth ‚jen·ə¦rā·shən ′laŋ·gwij]
(computer science)
A higher-level programming language that automates many of the basic functions that must be spelled out in conventional languages, and can obtain results with an order-of-magnitude less coding because of its richer content of commands.

fourth-generation language

A non-procedural programming language that requires less coding than lower-level languages. Command-line languages that come with operating systems and database management systems (DBMSs) are fourth-generation languages (4GLs), as are query languages and report writers. Any language with English-like commands that does not require traditional input-process-output logic falls into this category.

In addition, software tools that uses graphical interfaces for building applications or generating queries are also considered fourth generation. Underlying the menus and buttons are fourth-generation command structures that are activated with a click of the mouse.

First-, Second- and Third-Generation Languages
First-generation languages are binary machine languages. Second-generation languages are machine-dependent assembly languages, and third-generation languages (3GLs) are high-level programming languages, such as FORTRAN, COBOL, BASIC, Pascal, C/C++ and Java.

Many languages are actually a mix of both third- and fourth-generation languages. The following dBASE example shows the difference in syntax to open a customer file and display names and cities. In the 3GL language, the test for end of file and the loop to go back to the top and repeat the process are necessary. In second-generation languages, the specific screen columns must be identified. Contrast with non-procedural language. See compiler, machine language and assembly language.

dBASE                  dBASEProcedural             Non-Procedural3GL Language           4GL Language

 use customerFile       use customerFile
 do while .not. eof()   list name, city
   ? name, city
References in periodicals archive ?
According to Gary Green, senior manufacturing engineer of General Motors Corp, Buick-Oldsmobile-Cadillac Group, and Ralph Mackiewicz, VP, Systems Integration Specialists Co Inc (SISCO), we're throwing off the shackles of high-level tools such as fourth-generation languages (4GL).
The biggest change brought about by fourth-generation languages (4GLs) is that computer users today can make their requirements known to the computer in simple English and have the machine respond swiftly in kind.
* Fourth-generation languages facilitate the connection of many different files, joining them with common keys.