Dataflex
Encyclopedia
DataFlex is a relational database management system
Relational database management system
A relational database management system is a database management system that is based on the relational model as introduced by E. F. Codd. Most popular databases currently in use are based on the relational database model....

, self-described as an applications development database, originated around 1980.

It is a relatively early example of a fully fledged and commercially used fourth-generation programming language
Fourth-generation programming language
A fourth-generation programming language is a programming language or programming environment designed with a specific purpose in mind, such as the development of commercial business software. In the history of computer science, the 4GL followed the 3GL in an upward trend toward higher...

 (4GL). In its early forms, DataFlex was available for UNIX
Unix
Unix is a multitasking, multi-user computer operating system originally developed in 1969 by a group of AT&T employees at Bell Labs, including Ken Thompson, Dennis Ritchie, Brian Kernighan, Douglas McIlroy, and Joe Ossanna...

, VAX/VMS, TurboDOS
TurboDOS
TurboDOS is a multi user CP/M like operating system for the Z80 and 8086 CPU's developed by Software 2000 Inc.It was released around 1982 for S100 bus based systems such as the NorthStar Horizon.The multiprocessor nature of TurboDOS is its most unusual feature...

, Novell NetWare
Novell NetWare
NetWare is a network operating system developed by Novell, Inc. It initially used cooperative multitasking to run various services on a personal computer, with network protocols based on the archetypal Xerox Network Systems stack....

, CP/M
CP/M
CP/M was a mass-market operating system created for Intel 8080/85 based microcomputers by Gary Kildall of Digital Research, Inc...

, MS-DOS
MS-DOS
MS-DOS is an operating system for x86-based personal computers. It was the most commonly used member of the DOS family of operating systems, and was the main operating system for IBM PC compatible personal computers during the 1980s to the mid 1990s, until it was gradually superseded by operating...

 and OS/2
OS/2
OS/2 is a computer operating system, initially created by Microsoft and IBM, then later developed by IBM exclusively. The name stands for "Operating System/2," because it was introduced as part of the same generation change release as IBM's "Personal System/2 " line of second-generation personal...

 operating system
Operating system
An operating system is a set of programs that manage computer hardware resources and provide common services for application software. The operating system is the most important type of system software in a computer system...

s. DataFlex is produced by the Data Access Corporation located in Miami. Data Access Corporation was founded in 1976.

To date, DataFlex has lasted the course as a niche application development environment. The DataFlex product supports many database environments: Oracle
Oracle database
The Oracle Database is an object-relational database management system produced and marketed by Oracle Corporation....

, MS-SQL
Microsoft SQL Server
Microsoft SQL Server is a relational database server, developed by Microsoft: It is a software product whose primary function is to store and retrieve data as requested by other software applications, be it those on the same computer or those running on another computer across a network...

, IBM DB2
IBM DB2
The IBM DB2 Enterprise Server Edition is a relational model database server developed by IBM. It primarily runs on Unix , Linux, IBM i , z/OS and Windows servers. DB2 also powers the different IBM InfoSphere Warehouse editions...

, MySQL
MySQL
MySQL officially, but also commonly "My Sequel") is a relational database management system that runs as a server providing multi-user access to a number of databases. It is named after developer Michael Widenius' daughter, My...

 and Pervasive SQL as well as any ODBC database. DataFlex applications are used by around 3 million users worldwide.

The DataFlex programming language is used in the following development environments:
  • DataFlex - The latest iteration of the original character mode application is available as a Console Mode application for MS-DOS
    MS-DOS
    MS-DOS is an operating system for x86-based personal computers. It was the most commonly used member of the DOS family of operating systems, and was the main operating system for IBM PC compatible personal computers during the 1980s to the mid 1990s, until it was gradually superseded by operating...

    , Microsoft Windows
    Microsoft Windows
    Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...

     and Unix
    Unix
    Unix is a multitasking, multi-user computer operating system originally developed in 1969 by a group of AT&T employees at Bell Labs, including Ken Thompson, Dennis Ritchie, Brian Kernighan, Douglas McIlroy, and Joe Ossanna...

     variants (notably Linux
    Linux
    Linux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...

    ).
  • Visual DataFlex
    Visual DataFlex
    Visual DataFlex is a 4GL windows programming language by Data Access, targeted at creating database and client-server type programs.- Architecture :Visual DataFlex has a 3-layer architecture:Bottom layer: At this level you have the database tables....

     - This is the flagship development environment from Data Access Corporation. The current version is 16.1 (2011) VDF is available for Microsoft Windows
    Microsoft Windows
    Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...

     only. Visual Dataflex is a GUI
    Gui
    Gui or guee is a generic term to refer to grilled dishes in Korean cuisine. These most commonly have meat or fish as their primary ingredient, but may in some cases also comprise grilled vegetables or other vegetarian ingredients. The term derives from the verb, "gupda" in Korean, which literally...

     development language in a style comparable with Visual Basic
    Visual Basic
    Visual Basic is the third-generation event-driven programming language and integrated development environment from Microsoft for its COM programming model...

    , Delphi and C++
    C++
    C++ is a statically typed, free-form, multi-paradigm, compiled, general-purpose programming language. It is regarded as an intermediate-level language, as it comprises a combination of both high-level and low-level language features. It was developed by Bjarne Stroustrup starting in 1979 at Bell...

    .
  • WebApp Server - Available for Microsoft IIS and ASP
    Active Server Pages
    Active Server Pages , also known as Classic ASP or ASP Classic, was Microsoft's first server-side script engine for dynamically-generated Web pages. Initially released as an add-on to Internet Information Services via the Windows NT 4.0 Option Pack Active Server Pages (ASP), also known as Classic...

     only. WebApp Server can be used to develop thin client applications such as browser based applications (both full class browsers such as Internet Explorer
    Internet Explorer
    Windows Internet Explorer is a series of graphical web browsers developed by Microsoft and included as part of the Microsoft Windows line of operating systems, starting in 1995. It was first released as part of the add-on package Plus! for Windows 95 that year...

    , Mozilla Firefox
    Mozilla Firefox
    Mozilla Firefox is a free and open source web browser descended from the Mozilla Application Suite and managed by Mozilla Corporation. , Firefox is the second most widely used browser, with approximately 25% of worldwide usage share of web browsers...

     and Opera
    Opera (web browser)
    Opera is a web browser and Internet suite developed by Opera Software with over 200 million users worldwide. The browser handles common Internet-related tasks such as displaying web sites, sending and receiving e-mail messages, managing contacts, chatting on IRC, downloading files via BitTorrent,...

    , as well as WAP
    Wireless Application Protocol
    Wireless Application Protocol is a technical standard for accessing information over a mobile wireless network.A WAP browser is a web browser for mobile devices such as mobile phones that uses the protocol.Before the introduction of WAP, mobile service providers had limited opportunities to offer...

     browsers). Developers can also create Web Service
    Web service
    A Web service is a method of communication between two electronic devices over the web.The W3C defines a "Web service" as "a software system designed to support interoperable machine-to-machine interaction over a network". It has an interface described in a machine-processable format...

     client and server applications.


The DataFlex language differentiates itself from other programming languages in the following ways:
  • Easy switch between database backends, no code change needed. No compilation needed.
  • Variables are loosely typed. The virtual machine takes care of conversions.
  • Flexibility; you can define your own commands.
  • Code compiles to an intermediate byte-code
    Bytecode
    Bytecode, also known as p-code , is a term which has been used to denote various forms of instruction sets designed for efficient execution by a software interpreter as well as being suitable for further compilation into machine code...

     which makes the programs easily portable between operating systems.
  • No threads
    Thread (computer science)
    In computer science, a thread of execution is the smallest unit of processing that can be scheduled by an operating system. The implementation of threads and processes differs from one operating system to another, but in most cases, a thread is contained inside a process...

     or multitasking
    Computer multitasking
    In computing, multitasking is a method where multiple tasks, also known as processes, share common processing resources such as a CPU. In the case of a computer with a single CPU, only one task is said to be running at any point in time, meaning that the CPU is actively executing instructions for...

  • Methods can be defined or redefined inside the object definition.
  • Automatic delegation of messages in the object-oriented programming
    Object-oriented programming
    Object-oriented programming is a programming paradigm using "objects" – data structures consisting of data fields and methods together with their interactions – to design applications and computer programs. Programming techniques may include features such as data abstraction,...

     environment
  • Embedded Database access is ISAM
    ISAM
    ISAM stands for Indexed Sequential Access Method, a method for indexing data for fast retrieval. ISAM was originally developed by IBM for mainframe computers...

    based. Can be used royalty free.

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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