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DB/C DX, DATABUS, and PL/B OverviewDB/C DX is a program development tool for the DATABUS programming language.DB/C DX includes the compiler, the run-time executive and eighteen utilities. The utilities provide functions such as file management, file sorting, file indexing, library management, source file editing and more. DB/C DX is available for a variety of different computer operating systems including Windows 95 through XP based personal computers, LINUX, most UNIX computer systems, and Apple Mac OS X. What is DATABUS? DATABUS was created by Datapoint Corporation in the early 1970s. Until 1981, Datapoint was the only company providing a DATABUS compiler. Since then, at least six other companies have written and are currently marketing compilers for the DATABUS language. DATABUS was accepted as an ANSI standard in December 1994. In the process it was given the name PL/B because Datapoint refused to relinquish its trademark on the name DATABUS. People still generally refer to it as DATABUS. Why use DATABUS? The syntax is English-like and there are no cryptic characters to remember. But don't let this fool you—DATABUS contains over 125 separate operations (called verbs) that provide the competent programmer with an arsenal of functions. Here is an example of typical DATABUS code:
.
. THIS PL/B CODE FRAGMENT WILL LOOK UP THE
. TELEPHONE NUMBER OF AN EMPLOYEE BY EMPLOYEE NUMBER
.
LOOP
KEYIN "ENTER AN EMPLOYEE NUMBER: ", EMPNUM
STOP IF F3
READ EMPLOYEE, EMPNUM; NAME, TELNUM
IF OVER
BEEP
DISPLAY "EMPLOYEE NUMBER NOT ON FILE"
ELSE
DISPLAY "NAME: ", NAME, "TELEPHONE: ", TELNUM
ENDIF
REPEAT
Many business languages in use today were really designed for mainframe batch operation or single user PC operation. The aspect of multiple users accessing common files interactively is only an add-on in these languages. However, DATABUS was designed from the beginning to be run in an interactive, multi-user environment. The functions available to the programmer for screen display and keyboard handling are excellent. The data access and locking mechanisms are time tested and stand up well in a high performance, heavy usage operation. DATABUS is also a fine complement to SQL based database systems. Even though most SQL database systems come with a built-in 4GL, many database applications are still being written in a third generation language. The reasons for this vary, but the bottom line is that a 4GL is not capable of providing a programmer with all the functions that a third generation language provides. When the choice comes down to COBOL, C/C++, Java, VB, or DATABUS, many developers are choosing DATABUS. Here are some of the many reasons why development in DATABUS is superior:
1. Compilation is extremely fast and there is no link step at all. Why should I choose DB/C? The most important feature to understand about DB/C DX is its portability. No other language in existence today provides better portability than DB/C DX. The reason we can make this statement is simple:
Programs compiled under DB/C DX can be run on any supported computer without recompilation. This level of portability provides you with an unprecedented ability to run your applications software on almost any computer you choose - with the guarantee that it will run correctly without any program changes or other programmer intervention. If you currently have DATABUS programs written for Datapoint's RMS DATABUS or DOS DATASHARE systems, porting to DB/C DX is quick and simple. Certain features of DB/C make the conversion from the Datapoint dialects of DATABUS easier. Using DB/C DX, development and testing of new or existing DATABUS programs is noticeably enhanced from what is available with other DATABUS compilers. Compilation speed is typically hundreds of thousands of lines per minute. Coupled with the fact that there is no link step, total compilation time is faster than any other general-use compiled language in existence. An entire system such as an order entry system consisting of 50 programs can be compiled in less than a minute on a Pentium based computer. On more expensive UNIX systems, compilation is even faster. Is choosing DB/C DX prudent? Boeing Corp.
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