Paradox (database)

Paradox is a relational database management system currently published by Corel Corporation. It was originally released for MS-DOS by Ansa Software, and then by Borland after it bought the company. A Windows version was released by Borland in 1992.

Paradox for DOS was a relational database management system originally written by Richard Schwartz and Robert Shostak (brother of Seth Shostak) and released by their company Ansa Software in 1985. In September 1987, Borland purchased Ansa Software, including their Paradox/DOS 2.0 software. Notable classic versions were 3.5 and 4.5. Versions up to 3.5 were evolutions from 1.0. Version 4.0 and 4.5 were retooled in the Borland C++ windowing toolkit and used a different extended memory access scheme.

Paradox/DOS was a successful DOS-based database of the late 1980s and early 1990s. At that time, dBase and its xBase clones (Foxpro, Clipper) dominated the market. Other notable competitors were Clarion, DataEase, R:Base, and DataFlex.

The features that distinguished Paradox/DOS were:

Paradox for Windows is a distinctly different product from Paradox for DOS, and was produced by a different team of programmers. Although key features of the DOS product, the QBE and the database engine, were ports keeping the DOS code, there was a major break in compatibility from PAL to ObjectPAL and in the shift to a GUI design metaphor for Forms and Reports. The ObjectPAL changes were controversial but forced since PAL was based on keystroke recording actions that had no equivalent in Windows. An object-based language based on ideas from Hypercard was used in place of keystroke recording. The Forms and Reports designers used device independent scaling including ability to work in zoomed mode for detailed layout. The mouse right-click was used for access to Forms and Reports properties, inspired by the Xerox Alto and Smalltalk, in a way now almost universal to Windows programs. The ObjectPAL was (like Hypercard) associated with the visual objects - also revealed by right click. Property inspection and layout tools could be "pinned up" to stay on screen, an idea borrowed from the NeXT and now fairly widely adopted in Windows.

...
Wikipedia