| Navigation: ISAM File Drivers > Clarion Database Driver >====== Clarion Database Driver ====== |    |
Choosing the Right Database Driver
Common Database Driver Features
Clarion:File Specifications/Maximums
Clarion:Supported Commands and Attributes
Clarion:Specifications
The Clarion file driver is compatible with the file system used by Clarion for DOS 3.1 and Clarion Professional Developer 2.1, patch 2.109 and later.
Keys and Indexes exist as separate files from the data file. Keys are dynamic–they are automatically updated as the data file changes. The default file extension for a key file is *.K##. Indexes are static–they do not automatically update, but instead require the BUILD statement for updating.
The driver stores records as fixed length. It stores memo fields in a separate file. The memo file defaults to the first eight characters of the File Label plus an extension of .MEM.
| Files: | ClaCLAL.LIB | Windows Static Link Library |
| ClaCLA.LIB | Windows Export Library | |
| ClaCLA.DLL | Windows Dynamic Link Library |
By avoiding the ASCII-only file formats of many other popular PC database application development systems, the Clarion file format provides a more secure means of storing data.
Clarion:Data Types
| BYTE | DECIMAL |
| SHORT | STRING(255 byte maximum) |
| LONG | MEMO |
| REAL | GROUP |
Clarion:File Specifications/Maximums
File Size: 4,294,967,295
Records per File : 4,294,967,295
Record Size: 65,520 bytes
Field Size : 65,520 bytes
Field Name: 12 characters
Fields per Record: 65,520
Keys/Indexes per File: 251
Key Size: 245 bytes
Memo fields per File : 1
Memo Field Size: 65,520 bytes
Open Data Files: Operating system dependent
A Clarion file name (including path) cannot be longer than 79 characters.