The DATASET data type may be associated with any known schema. You can provide a schema based on frequently used structures, which are stored in the Data Dictionary. All DATASET functionality is available to storage formats using any schema that conforms to specifications for that storage format. After it is registered, any schema can be referenced using the WITH SCHEMA <name> clause.
You cannot specify the WITH SCHEMA option when creating a volatile table.
No built-in schemas are provided for use with DATASET, in any of its storage formats.