In V11 and later, user-defined conditional expressions can be used for partition rules, as described in the next section.
Legacy Versions
The partition key can be set when the file is created using the prtkey parameter of the extended file creation block. This value defaults to 0, indicating the first key associated with the data file. Set this value to the relative key number for the desired index if the default is not appropriate for your application.
The default rule, developed for testing purposes only, uses a simple algorithm to divide added records into partitions based on the first byte of the selected key as a test of the partition capability. See the function kprawno() in ctpart.c for the sample algorithm.
Cautions and Restrictions
See "Partition Ordering and Range Query" in Raw Partition Numbers for information on number generating rules.