Indexed File Size Limits

The following file size limits affect indexed files:

To create files of a different format, use the IDXFORMAT extfh.cfg or compiler directive setting. To convert existing files to other formats, use the Rebuild utility.

IDXFORMAT Exclusive (#) Exclusive with duplicate key compression on Shared with default locking FILEMAXSIZE set to
1 4 Gb 2 Gb 1 Gb 4 or 8
2 4 Gb 2 Gb 1 Gb 4 or 8
3 4 Gb 2 Gb 1 Gb 4 or 8
4 4 Gb 2 Gb 1 Gb 4 or 8
8 4 Gb 2 Gb 1 Gb 4
8 256 Tb 128 Tb 256 Tb 8

where:

Note:
  • The above figures are determined by the pointer size used to address the file. For example:
    32 bits = 2^32 = 4,294,967,296 bytes = 4 Gb (Gigabytes)
    48 bits = 2^48 = 281,474,976,710,656 bytes = 256 Tb (Terabytes)
    64 bits = 2^64 = 18,446,744,073,709,551,616 bytes = 16 Eb (Exabytes or MegaTerabytes)
  • LOCKTYPE settings of 1 and 2 were specifically introduced in order to avoid the file size limit imposed by sharing files.
  • If you set FILEMAXSIZE to 8, IDXFORMAT 8 supports very large files with the default locking mechanism. Therefore, you are recommended to use IDXFORMAT 8 for large files rather than any of the other formats which also require LOCKTYPE 1 or 2 for large files. (LOCKTYPE=1 has the disadvantage of not allowing locked data to be read at all while LOCKTYPE=2 has the disadvantage of using up an extra file handle for the .LCK file that contains the locks).