Note
For OceanBase Database V4.2.x, this parameter was introduced in OceanBase Database V4.2.5.
Description
query_memory_limit_percentage specifies the maximum percentage of memory in the tenant available for a single SQL query. When the memory used by an SQL statement exceeds the specified value, the system returns an error and stops the SQL statement execution.
Limitations
Query the parameter
In the
systenant or a user tenant, you can execute theSHOW PARAMETERSstatement to query the parameter or query theGV$OB_PARAMETERSview for the parameter.Modify the parameter
You can modify the parameter in the
systenant or a user tenant.
Attributes
| Attribute | Description |
|---|---|
| Type | Integer |
| Default value | 50 |
| Value range | [0, 100] |
| Modifiable | Yes. You can use the ALTER SYSTEM SET statement to modify the parameter. |
| Effective upon OBServer node restart | No. The setting takes effect immediately. |
Examples
Set the maximum memory in the tenant available for a single SQL query to 50% of the tenant memory.
obclient> ALTER SYSTEM SET query_memory_limit_percentage = 50;