Progress
Database Administration
Guide and Reference
Calculating Database Disk Requirements
The Version 9 database engine stores all database fields and indexes in variable-length format and does not store trailing blanks in character fields or leading zeros in numeric fields. The benefits of this variable-length storage technique are:
Table 2–1 lists the formulas you use to calculate the approximate amount of disk space (in bytes) required for a database.
Table 2–1: Formulas For Calculating Database Size Size Formula Database size schema size + data table size + index size Schema size Typically, between 1 and 100MB1 Data table size Sum of individual table sizes Individual table size number of records x field storage x 1.5 Index size Sum of individual index sizes Individual index size number of records in the table being indexed x(7 + number of fields index +field storage) x 2
Table 2–2 lists the formulas you use to calculate the field storage values (in bytes) for different data types.
EXAMPLE
You want to calculate the estimated database size for a database with a single customer table. The table has three fields:
The table is indexed on just one field (Name) and you would expect to have about 500,000 records in the customer table. Table 2–3 lists formulas (and examples) for estimating the size of your database.
These formulas are conservative since they often result in a large estimate of your database size. However, you also must allow for temporary disk space for each database user for the following purposes:
Database-related Size Criteria
When planning the size of your database, see "Progress Database Limits," for a description of the following database-related criteria:
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