Specifies file compression.
Data compression can only be specified for an output file. Key compression can be specified for an output file or the rebuild of an existing file.
The /c option operates in a similar manner to the Compiler directives DATACOMPRESS and KEYCOMPRESS.
Parameters
-
d
n
- Data compression. n must be in the range 0 through 255:
| Value |
Description |
| 0 |
No data compression. |
| 1 through 127 |
Reserved. |
| 128 through 255 |
User-defined compression routines. |
-
i
n
- Key compression. n must be in the range 0 through 15:
| Value |
Description |
| 0 |
No key compression. |
| 1 |
Duplicates are compressed. |
| 2 |
Leading characters are compressed. |
| 4 |
Leading spaces are compressed. |
| 8 |
Trailing nulls are compressed. |
Note: You cannot compress the data in C-ISAM and Level 2 files.
Examples
-c:d1i6
specifies data compression routine 1, and index compression of leading characters and trailing spaces.
-c:i1
specifies key compression of duplicates only.
