Default Collection Metadata For Pre-26ai Collections

This section applies only to pre-26ai collections. If database parameter COMPATIBLE is 23 or higher, the default collection is a 26ai JSON collection table.

For 26ai JSON collection tables and views, metadata is not stored separately and is not used to configure the collection. Instead, it is synthesized on the fly so that SODA drivers can work with these collections. The synthesized metadata includes "native": true and is the same across all database types.

For pre-26ai collections, the defaults depend on the database type and also the value of initialization parameter COMPATIBLE:

If COMPATIBLE >= 20:
- contentColumn.sqlType is “JSON”
- versionColumn.method is “UUID”
If COMPATIBLE < 20 on an autonomous database:
- contentColumn.sqlType is “BLOB”
- contentColumn.jsonFormat is “OSON”
- versionColumn.method is “UUID”
If COMPATIBLE < 20 on a nonautonomous database:
- contentColumn.sqlType is “BLOB”, storing textual JSON data encoded as UTF-8 or UTF-16
- additional contentColumn fields are present: compress, cache, encrypt, and validation
- versionColumn.method is “SHA256”

Custom metadata can be defined as follows:

On an autonomous database:
- keyColumn.assignmentMethod can be changed to CLIENT
- on Autonomous Transaction Processing (ATP) and Autonomous Data Warehouse (ADW), but not Autonomous JSON Database (AJD), mediaTypeColumn.name can be added for heterogeneous collections
On a nonautonomous database:
- any metadata fields can be customized

Note: You need certain versions of SODA drivers and related software to support collection content type that uses Oracle’s native JSON binary format, OSON, that is, for JSON type or for BLOB type with format OSON. See SODA Drivers

Related Topics