dBASE
dBASE was the first widely used file-based database management system (DBMS) for microcomputers . It was originally developed and sold by Ashton-Tate for the CP / M operating system . The database application was later ported to the IBM PC under DOS .
The basic idea of the dBASE system is to keep the tables of a database in specially structured files (DataBaseFiles = DBF) and to provide a fourth generation programming language for processing .
The xBase standard
With its syntax and data structure, dBASE has created a quasi-standard that a number of companies have adopted for similar systems. The group of dBASE-compatible software products is often summarized with the term xBase .
For years, dBASE was one of the best-selling software titles under DOS. Its importance in the market only diminished when it was not possible to optimize dBase for Microsoft Windows quickly enough . Systems such as Paradox , FoxPro (now Visual FoxPro from Microsoft ), Xbase ++ and Vulcan.NET , which have retained the compatibility with the dBase data structures , initially took the place of dBase .
In 1991 the software house Ashton-Tate was bought by Borland to assert itself against Microsoft. Borland did not manage to maintain its market share, however. The rights to the dBase product line were sold to dBASE Inc. in 1999.
Instead, the rise of Office products under Microsoft Windows began at this time , which could process dBase files in addition to their own formats. Microsoft Access , in particular , was able to use dBASE files. Also Visual Basic for Windows had additional software drivers for dBASE files.
In recent years, database management systems such as Oracle , Microsoft SQL Server , PostgreSQL or MySQL have been used for new database applications in client-server systems , which meet the ACID properties and move away from the limitations of dBASE data structures and the concepts of file-based Database systems have solved.
dBase can read and create data from tables in CSV and SDF file formats.
Source code and compiler for dBase
Source texts similar to BASIC , which were created and executed in dBase and which made the automation of data processing beyond the purely interactive mode possible in the first place, were also responsible for the success of dBase . The company Nantucket Corporation was characterized by the then popular compiler Clipper , which was able to compile independently executable programs from dBase source code. This and similar compilers from other manufacturers also made it possible to access other database systems and mainframes using SQL using so-called database drivers. Ashton-Tate itself only released a compiler for version dBase IV.
The success of dBASE
Responsible for the great success of dBASE are the various competing and complementary software systems that also worked with dBASE files, the PC, which was initially barely networked, and the easy-to-learn integrated programming language.
With the integration of functions for databases in the network such as Novell NetWare , which made it possible to lock individual data records, dBASE IV became the market leader among file-based database systems. During this time, PPS systems and database-based specialist applications were primarily developed with dBase and Clipper.
Programs that used dBASE files were found almost everywhere on personal computers. Due to the interpreter concept, the applications were slower than native programs, so that dBASE was hardly used for computationally intensive numerical calculations. In addition, dBASE lacked a powerful graphics interface for a long time.
Use of dBASE today
dBASE was designed as a purely file-based database system and was initially only able to work efficiently with its own file format. In networks and multi-user environments, file-based database systems are inferior to the more powerful client-server model . A typical problem is competing write accesses to a data record.
dBASE files and programs are now considered technically obsolete, although the dBASE file format is still often used as a data exchange format for small databases. But here, too, more modern concepts such as XML are already state of the art.
The migration of existing dBASE programs under MS-DOS to Windows is possible in principle, but has rarely been implemented in practice, as the requirements for the user interface of DOS and Windows are very different in some areas.
Geographic information systems
dBASE III no longer plays a role in the database market today. It is only used in the field of geographic information systems (GIS) in the shape format developed by ESRI . When the file format was introduced in 1998, ESRI opted for a dBase III table (* .dbf file), which is used internally as an attribute file. The shape format has developed into a quasi-standard for the data exchange of vector data.
history
Beginnings
The history of dBASE goes back to the 1960s. The prevailing system at the time was RETRIEVE, which was developed by Tymshare Corporation . RETRIEVE was used by the Jet Propulsion Laboratory . Eventually the programmer of the project, Jeb Long , was hired to develop an adapted version. The derivative was named JPLDIS ( Jet Propulsion Laboratory Display Information System ). The code was written in Fortran and operated on the UNIVAC -1108 mainframe computers. From this, Wayne Ratliff later developed an adapted version called VULCAN (named after the home planet of Mr. Spock ), to which the Ashton-Tate company became aware.
dBASE II
Wayne Ratliff sold the marketing rights for the VULCAN programming language to Ashton-Tate, which hired him and Jeb Long as developers. This company ported VULCAN later to CP / M . Marketing called the product dBASE II in order to present it as an improved version of a non-existent original dBASE. The success came very quickly. As a result, the database management system was ported to many other 8-bit computer platforms including the Apple II version (CP / M with Z80 processor card) as dBASE II and sold.
Wayne Ratliff also programmed a 16-bit version for IBM-PC. In August 1982 dBASE II 2.3 came out and became one of the most successful software applications for PCs. There was also a version for the Atari ST with a graphical user interface for GEM .
Zip including Zip Talker was initially an optional utility program for dBase and MBASIC , developed by Hal Pawluk in 1982 and a short time later part of dBase II. As a form generator it extended u. A. the printer and monitor output on 88 instead of 24 lines. The file extensions .FMT, .CMD, .ZPR and .ZIP were used. The unit price was $ 160.
dBASE III (PLUS)
In the second half of the 1980s, Ashton-Tate achieved a 67% market share in PC database systems in the Federal Republic of Germany and neighboring countries with dBASE III and its successor, dBASE III PLUS . These two versions were supported by Clipper , the dBASE compiler from Nantucket Corporation , with which developers could create executable EXE files for customers from the dBASE source text files (* .PRG), which ran particularly quickly under DOS and enabled them to be used without the customer having to purchase dBASE or the required runtime module. Furthermore, no source text had to be given outside.
With the advent of PC network software such as Novell NetWare , dBASE III PLUS was expanded to include network commands such as: B. LOCK / UNLOCK RECORD extended to be multi-user capable . New versions of Clipper also support these commands.
The fact that dBASE had defined interfaces to Office programs such as Lotus 1-2-3 and Microsoft Word made it possible for the developer to transfer data in both directions.
dBASE III (like dBASE II and other successful standard software) was cloned by the GDR company Robotron and sold in the GDR under the name Redabas .
Ashton-Tate's biggest competitor was Borland with its PARADOX database system , but it never reached dBASE's market share. All PARADOX databases support the dBASE data format and had defined interfaces to dBASE to enable the changeover.
In 1986 Ashton-Tate began developing software for the Apple Macintosh . A smaller company developing business applications, Ann Arbor Softworks , was purchased. An office package with the Full Impact spreadsheet , a word processor called FullWrite Professional and a database application called dBASE Mac were produced here.
The project was a failure, only dBASE Mac remained as an application, with a graphical user interface. File sharing with the PC versions was impossible, however, and the competition with other Mac databases was at the expense of dBase Mac.
dBASE IV
Ashton-Tate's demise began with dBASE IV . The first release appeared in the US in October 1988. dBASE IV 1.0 already had embedded SQL and an integrated pre-compiler.
The US version had many bugs and had to struggle with the 640 KB memory limit of the industrial standard for PCs that was valid at the time. In addition, even the compiled programs were slower than the uncompiled programs in dBASE III +. The new control center for operating dBASE IV turned out to be a flop because the clerks and secretaries in the company couldn't cope with it. The newly developed report and label generator was difficult to use.
From mid-1990 dBase IV 1.1 was also offered for SCO Unix and SunOS .
In 1991 Ashton-Tate was bought by its biggest competitor Borland .
Borland dBASE
Borland continued dBASE IV as Borland dBASE with the releases 1.1, 1.5 and - as a bridge to dBASE for Windows - with the release dBASE IV 2.0. In addition, the in-house dBASE compiler 1.0 was developed for MS-DOS, which supported dBASE up to dBASE IV 2.0.
dBASE 5.0 appeared again in 1993 under DOS and Windows. However, like its predecessor, it could no longer really assert itself on the market. The competitor product Access released by Microsoft in October 1992 , which was based on dBase in terms of operation, was able to oust dBase as the market leader for file-based databases by 1996 (source: PC-Welt July 1996).
dBASE on Windows
Borland also introduced new versions of dBase for Windows. The first dBase Windows version around the mid-1990s was called dBase for Windows (V 5.0) and was still programmed for the 16-bit Windows versions (specifically Windows 3.x). For the first porting from DOS to Windows it worked out quite well, even if the performance and stability were not always convincing. Then came Visual dBase (V 5.5), also still in 16-bit technology, followed by V 5.7 under the same name and for the first time year 2000 capable.
The first 32-bit versions were also offered as Visual dBase , but under the version number 7.0x and went up to V 7.5x.
In the new millennium, after the rights to dBase Inc. were sold, the product was available under the name dBase 2000 or dB2K with versions 0.1, 0.2, 0.3 and 0.4.
dBASE Plus
From around 2004/2005 the product was owned by DataBased Intelligence Inc. (dBI), which continued to maintain and market it under the name dBASE Plus . In 2012 the rights to dBASE Plus again went to the newly founded company dBase LLC , which is partly composed of former dBI employees.
dBASE Plus is a powerful database system under Windows and can run PRG files directly (as previously under DOS using an interpreter) and create independent EXE programs (with the help of the integrated compiler). Numerous old xBase commands for processing databases such as use , replace , append etc. work with it as they did decades ago. But object-oriented programming is also possible.
In June 2011 the version dBASE Plus 2.70 was released . Compared to its predecessors, it runs more stably under Windows 7 and Windows Vista, especially the 64-bit versions, and offers, among other extensions, improved support for Windows User Account Control (UAC).
From June 2015 the version dBASE Plus 10 was offered. It contains an object-oriented programming language (dBL) and runs on 32 and 64-bit versions of Windows. DBASE Plus 11 has been available since December 2016. The main innovation is support for touch and tablets.
literature
- Anton Kehl: dBase 5.0 for Windows. The compendium. Introduction, workbook, reference book. , Pearson Education, Munich 1998, ISBN 3-87791-661-9
- Ulf Neubert: dBASE is alive! - Volume 1, Introduction , BoD, November 2005, ISBN 3-8334-3948-3
- Ulf Neubert: dBASE is alive! - Volume 2, Basics , BoD, November 2005, ISBN 3-8334-3949-1
- Ulf Neubert: dBASE is alive! - Volume 3, Classes and Objects , BoD, October 2006, ISBN 3-8334-6307-4
Web links
- dBASE Inc. (English)
- dBase file format
- dB-DA-CH the German user group
- Lutz Conrad dBase Tools in German
Individual evidence
- ↑ Info World Vol 4, No. 31
- ↑ dBase to Create Business Intelligence Software for Small Business at dbase.com, added Sept. 8, 2013
- ↑ http://www.dbase.com/ dbase-Homepage
- ↑ http://www.dbase.com/FeaturesAndFixes2_61_5.asp
- ↑ http://www.dbase.com/dbasesql/overview/
- ^ DBase, LLC. Introduces dBASE ™ PLUS 11, Empowering Developers with Touch. In: dbase.com. dBase, LLC, December 14, 2016, accessed January 7, 2017 .