Updating Statistics on an Index Partition

Maintaining statistics on index partitions can improve the performance of many queries.

1. In the Administration Console view, select ASE Servers > Schema Objects > Tables > User Tables.
2. Select the table that contains the index and index partitions on which to run update statistics.
3. Click Properties.
   You see the Table Properties screen.
4. Select the Indexes screen.
5. Select the index on which to run update statistics and click Properties.
   You see the Index Properties screen.
6. Select the Index Partition screen.
7. Select the index partition on which to run update statistics.
8. Select Update Statistics to start the Update Statistics wizard.
9. On the Command Type screen, select the update statistics command to run.
10. On the Hashing screen, select:
    • The type of hashing:
      • Partial hashing – for columns that have 65536 or fewer unique values.
      • With hashing – for columns that have greater than 65536 unique values.
      • No hashing.
    • A value for max resource granularity (which indicates the maximum percentage of the system’s resources a query can use), if applicable.
11. Click Next.
12. On the Histogram Tuning screen, set the histogram tuning factor. The size of the histogram is established by multiplying the number of steps with the value for histogram tuning factor.
13. Click Next.
14. On the Sampling screen, specify whether to set sampling, and to what percentage.
15. Click Next.
16. On the Step Number screen, indicate if you want to set the number of histogram steps, and how many.
17. Click Next.
18. On the Summary screen, verify your selections.
19. Click Finish.