2.216 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 COMPATIBLE initialization parameter must be set to 23.0.0.0 or higher in order to set MAX_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.