Oracle object datatypes

What are object datatypes? Explain the use of object datatypes.

- Object data types are user defined data types.

- Both column and row can represent an object type.

- Object types instance can be stored in the database.

- Object datatypes make it easier to work with complex data, such as images, audio, and video.

- Object types provide higher-level ways to organize and access data in the database.

- An object type differs from native SQL datatypes in that it is user-defined, and it specifies both the underlying persistent data (attributes) and the related behaviors (methods).

- Object types are abstractions of the real-world entities, for example, purchase orders.

- Object types store structured business data in its natural form and allow applications to retrieve it that way.

- Object types and related object-oriented features, such as variable-length arrays and nested tables, provide higher-level ways to organize and access data in the database.

- Underneath the object layer, data is still stored in columns and tables, but work can be done with the data in terms of the real-world entities--customers and purchase orders, for example--that make the data meaningful.

- Instead of thinking in terms of columns and tables when a database is queried , just select a column.

- Internally, statements about objects are still basically statements about relational tables and columns, and work can be continued with relational datatypes and store data in relational tables. But there is an option to take advantage of object-oriented features too.

- Object-oriented features can be used while continuing to work with most of your relational data, or can go over to an object-oriented approach entirely.

- For instance, define some object datatypes and store the objects in columns in relational tables.

- Object views can be created of existing relational data to represent and access this data according to an object model or you can store object data in object tables, where each row is an object.
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