Note
This variable is available starting with V4.5.0 for V4.5.x.
Description
ob_ivf_nprobes specifies the number of nearest cluster centers to search for during a vector index query. This variable affects the performance and recall rate of IVF queries: a larger value increases the recall rate but also increases the search time.
Applicability
This variable is applicable only to OceanBase Database in MySQL mode.
Privilege requirements
Query variables
- The
systenant and all user tenants can execute theSHOW VARIABLESstatement or query theinformation_schema.SESSION_VARIABLESview (MySQL mode) to view the values of session system variables.
- The
Modify variables
- The
systenant and all MySQL user tenants can directly modify the values of session system variables in their own tenant.
- The
Attributes
| Attribute | Description |
|---|---|
| Type | Int |
| Default value | 8 |
| Value range | [1,65536] |
| Scope | Session |
| Modifiable | Yes. You can execute the SET statement to modify the value. |
Examples
Set the number of nearest cluster centers to search for in this query to 10.
obclient> SET ob_ivf_nprobes = 10;