Purpose
Specifies whether Teradata Database should determine the appropriate amount of table data to sample for statistics collection. If not, the sample size will be 100%.
This field is used only when a COLLECT STATISTICS SQL statement does not specify the USING SAMPLE option.
Field Group
Optimizer Statistics
Valid Settings
| Setting | Description |
|---|---|
| 0 | Use factory default, currently equivalent to setting 1. |
| 1 | Enables system-determined sample percentage up to 100%. |
| 2 | Sample percentage is 100% (full statistics). |
Default
0
Changes Take Effect
After the DBS Control Record has been written.
Usage Notes
Statistics are used by the optimizer to improve query performance.
When cost profiles are in effect, this field can be overridden by a cost profile constant value.
Related Topics
| For more information on… | See… |
|---|---|
| Optimizer statistics fields | |
| Cost profiles |
|