MAX_COLUMNS
Use MAX_COLUMNS to enable or disable Wide Tables for the database.
| Property | Description |
|---|---|
| Parameter type | String |
| Syntax | MAX_COLUMNS = { STANDARD | EXTENDED } |
| Default value | STANDARD |
| Modifiable | No |
| Modifiable in a PDB | Yes |
| Basic | No |
| Oracle RAC | Multiple instances must use the same value. |
Values:
-
To enable Wide Tables, set this parameter to
EXTENDED. With this setting, the maximum number of columns allowed in a database table or view is 4096.The
COMPATIBLEinitialization parameter must be set to23.0.0.0or higher in order to setMAX_COLUMNS=EXTENDED. -
To disable Wide Tables, set this parameter to
STANDARD. With this setting, the maximum number of columns allowed in a database table or view is 1000. This matches the behavior in releases prior to Oracle AI Database 26ai.
You can change the value of MAX_COLUMNS from STANDARD to EXTENDED at any time. However, you can change the value of MAX_COLUMNS from EXTENDED to STANDARD only when all tables and views in the database contain 1000 or fewer columns.
Note: The increased column limit of 4096 is supported by Oracle AI Database 26ai clients, such as SQL*Plus, OCI, JDBC-OCI, unmanaged ODP.NET, and open source drivers. Older client versions (pre-Oracle AI Database 26ai) do not support the increased column limit and cannot access more than 1000 columns in a table or view.
Note: This parameter is available starting with Oracle AI Database 26ai.