Progress
Database Administration
Guide and Reference
PROUTIL TABANALYS Qualifier
Displays information about the degree of fragmentation for each table in a database. Also displays summary information about record sizes for each table.
SYNTAX
db-name
Specifies the database to display information.
EXAMPLEThe following is a sample display of PROUTIL TABANALYS output:
DISPLAY FIELDS
Table
Table owner and table name.
Records
Total number of records in the database for the table.
Bytes
Total number of bytes used in the database for the table.
Min
Minimum number of bytes used by any record for the table.
Max
Maximum number of bytes used by any record for the table.
Mean
Mean number of bytes used by any record for the table.
Count
Total number of record fragments found in the database for the table.
Factor
Degree of record fragmentation for the table. This value is determined by the number of fragments divided by the ideal number of fragments (for example, if the data were freshly loaded). A value of 1.0 is ideal. A value of 2.0 indicates that there are twice as many fragments as there would be if the data were freshly loaded.
Use the Index value to determine whether to dump and reload your data to improve fragmentation. If the value is 2.0 or greater, dumping and reloading will improve performance. If the value is less than 1.5, dumping and reloading is not warranted.
Scatter Factor
Degree of distance between records in the table.
The best achievable Scatter Index value is that of a freshly loaded database. This is the baseline number against which you should compare future Scatter Index measurements. A value of 1 indicates that the records occupy completely contiguous database blocks. A value of 2 indicates that the records are scattered 10 times wider than the ideal.
Use this value to determine the performance impact caused by fragmentation. If the value is 1.5 or greater, performance will be poor for sequential record access, and dumping and loading the data might be warranted. A value of 1.5 or greater might also reduce performance for random access; however, this depends on the system type and the application.
NOTES
- The PROUTIL DBANALYS display includes the information displayed by PROUTIL TABANALYS.
- See "Managing Performance," for more information about database fragmentation.
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