sindex - print summary of RMS index file usage
[Requires: C/Base Utilities Module]
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 spliting 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.