The DBMS_METADATA package

The DBMS_METADATA package was introduced in Oracle 9i. The API enables the extraction of object metadata from database dictionaries that can be optionally manipulated and re-executed on a database server. The package is owned by SYS whose public synonym is used by all users. A user with SELECT_CATALOG_ROLE can directly access the DBMS_METADATA package.

Note

DBMS_METADATA is a key enabler of metadata export functionality in Data Pump

The package pulls the object's metadata in XML form from the database dictionary and provides transform handlers to build it in the desired form. The formatted XML can then be re-executed in the database.

DBMS_METADATA data types and subprograms

As we said earlier, the DBMS_METADATA package uses the public synonyms of SYS-owned data structures. The following list shows SYS-owned object types:

• SYS.KU$_PARSED_ITEM: An object type used to capture the attributes of an object's metadata. The object type structure is as follows:

  CREATE TYPE sys.ku...