Types of large objects in oracle

Explain types of large objects in oracle, i.e. BLOB, LLOB,NCLOB and BFILE.

Internal LOBs:
BLOBs, CLOBs, and NCLOBs are Internal LOBs stored inside database tablespaces to optimize space and efficient access. Changes to internal LOBs can be committed or rolled back.

They use copy semantics and participate in the transactional model of the server and can be recovered on media failure.

The ACIDFoot 1 properties are applicable to internal LOBs too.

The BLOB data type stores binary large objects. BLOB can store up to 4 gigabytes of binary data.

The CBLOB data type stores character large objects. CLOB can store up to 4 gigabytes of character data.

The NCBLOB data type stores character large objects in multibyte national character set. NCLOB can store up to 4 gigabytes of character data.

External LOBs:

BFILES are External LOBs stored in operating system files outside database tablespaces. These files use reference semantics.

The BFILE datatype allows read-only byte stream access to large files on the file system of the database server. The maximum file size supported is 4 gigabytes.
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