Document Type | Technical Information
Category | Tuning
Applicable Product Versions | 6FS07, 6FS07PS, 7FS02, 7FS02PS, 5SP1FS06, 6FS06, 6FS07, 6FS07PS, 7FS02, 7FS02PS
Document Number | TTUTI004
Overview
This provides the numerical values and settings based on the manual for the main parameters used in the DBMS_STATS package.
Method
estimate_percent
If 0 is entered, the optimizer determines an appropriate sampling rate according to the table size and executes accordingly. The criteria for setting are as follows.
- If the table has 1,000,000 or more rows: 100,000 / number of rows * 100 (%)
- If the table has 10,000 to 1,000,000 rows: 10%
- Less than that: 100%
GATHER AUTO
Only tables that need to be collected according to internal criteria are collected. The collection target meets the following criteria.
- Tables that have not had statistics collected
- Tables where the last statistics collection showed zero rows
- More than 10% change
ใด Applies only to insert and delete statements
ใด For this condition, the _GATHER_DML_STAT=Y parameter needs to be applied (default value is N)
- Tables where the statistics collection time has passed a certain period (default: 1 week)
NoteParameters other than those described can be found in the Tibero manual > Tibero tbPSM Reference Guide > 45. DBMS_STATS.