Note
This parameter was introduced in V2.2.50.
Description
In shared-nothing (SN) mode, the
datafile_sizeparameter specifies the size of data files.In shared-storage (SS) mode, the
datafile_sizeparameter specifies the size of local cache space.
Privilege requirements
Query privilege
Tenants in the
systenant and all user tenants can use theSHOW PARAMETERSstatement or theGV$OB_PARAMETERSview to query this parameter.Modify privilege
Only the
systenant can modify this parameter. User tenants are not allowed to modify it.
Attributes
| Attribute | Description |
|---|---|
| Type | Capacity |
| Default value | 0M. The default unit is MB. Specify the unit when you modify the parameter. |
| Value range | [0M, +∞) |
| Modifiable | Yes. You can use the ALTER SYSTEM SET statement to modify it. |
| Effective upon OBServer node restart | No. The setting takes effect immediately. |
Considerations
- Once this parameter is set, it can only be increased and cannot be decreased.
- If this parameter and
datafile_disk_percentageare configured, the value of this parameter takes precedence. For more information aboutdatafile_disk_percentage, see datafile_disk_percentage.
Example
In shared-storage mode, set the size of data files to 80 GB.
obclient> ALTER SYSTEM SET datafile_size='80G';