deletions. Similarly, the utilization rates vary depending on these factors for the data and index parts of a BTREE
structure and the overflow rate of a RANDOM structure. (The overflow rate of a RANDOM structure is the rate of
overflow to the overflow part relative to the total number of records.) When estimating the amounts of space needed,
use the following kinds of criteria for the various values in the formulas.
If the number of records in a page is small, the various utilization rates are lower, and the overflow rate is higher.
Key compression rate criteria
The key is compressed and stored in the BTREE structure data part and index part. Use the following kinds of criteria
for the key compression rates in the formulas:
Example 1:
Estimate of the required amount of space for a SEQUENTIAL structure
Calculate the required amount of space for the ORDER table (total number of records: 30,000) having
this kind of structure:
Storage structure:
SEQUENTIAL structure
Page size:
32 kilobytes
Safety factor:
1.3
161