sindex - print summary of RMS index file usage


sindex datafile [ index# ]


Sindex prints out summary information about usage of an RMS index file. Datafile is the name of a C/Base RMSfile which uses an RMS index file. If index# is omitted, the primary key fields (if indexed) and all secondary keys are analyzed. When index# is specified, only that index is analyzed. If index# is specified as zero (0), the primary key fields (if indexed) are analyzed.

The output from sindex gives statistical data about how the keys are stored in each index. The first column shows the index being analyzed. The second column gives the maximum depth of the index tree. The next column shows the total number of keys stored in the index. This number should be the same for all indexes of one RMSfile. The fourth column displays the total number of index pages used by an index. Currently, each index page is 512 bytes.

The last column gives a figure called a load factor. Load factors indicate how well keys are packed into the index tree. A load factor of 100 indicates that all available key slots are filled. A load factor of 50 indicates that only half of the available slots are used. When a load factor is high, insertions cause more page splitting but searches and deletions go faster. When load factors are low, insertions go faster, but searches and deletions take longer.


This command is available only with the C/Base Utilities software package.