Corel WordPerfect Office is a productivity suite that rivals Microsoft Office. In WordPerfect Office, the equivalent of Microsoft's Access database application is called Paradox. Paradox is a relational database management system that stores normalized data in tables. The structure of the database, database objects and the data in the database are all held in different files. Paradox has its own native file extensions and is also able to handle files common to other
applications.
Non-native Files
- The DBF file extension was originally used by dBASE. dBASE was an early success in the desktop database market, but failed to adapt to the Windows operating system. It was eventually integrated into the development of Paradox. Although Paradox has its own native file extension for database, it accepts files with the DBF file extension, as to many other desktop relational database applications, including FoxPro and Access. dBASE came into Corel's possession through its take over of WordPerfect, which had taken over Borland Software Corporation. Borland used the DM file extension for data models that could be used by a number of its applications. It programmed this capability into Paradox during its period as the owner of the application. Borland also integrated capabilities to access the Borland Database Engine into Paradox. This uses the GDB file extension.
Standard Database Files
- The core file of a Paradox database has the DB file extension. This file replaced the T file extension. Extra information about the database structure is stored in a file with the XGO file extension. Access to database files is controlled by the presence of a lock file, which has the LCK file extension.
Table Files
- Although the DB file contains the table structures of a Paradox database, other table-related data is stored separately. Views are pseudo tables composed from stored queries. Table views are stored in a file with the TV file extension. The data in the tables is stored in a file with the PD file extension. The Paradox system contains two more file extensions that relate to table functions. A DF file contains table filters and a VAL file holds referential integrity checks.
Indexing
- The majority of the file extensions used for a Paradox database relate to indexing. The storage of primary indexes on tables involves a file with the PX file extension. Secondary indexes, however are stored in files with 29 different file extensions. These are X01 to X09, XG0 to XG5, Y01 to Y09 and YG0 to YG4. Data sorting generates a file with the SOM file extension.
