|Oracle 8i Data Cartridge Developer's Guide
Release 2 (8.1.6)
Part Number A76937-01
Working with Multimedia Datatypes, 2 of 10
Some data cartridges need to handle large amounts of raw binary data, such as graphic images or sound waveforms, or character data, such as text or streams of numbers. Oracle8i supports large objects (
LOBs) to handle these kinds of data.
Internal LOBs are stored in the database tablespaces in way that optimizes space and provides efficient access. Internal
LOBs participate in the transactional model of the server. External
LOBs are stored in operating system files outside the database tablespaces. External
LOBs do not participate in transactions.
LOBs can store binary data (
BLOBs), single-byte character data (
CLOBs), or fixed-width single-byte or multibyte character data (
NCLOB consists of character data that corresponds to the national character set defined for the Oracle database. Varying-width character data is not supported in Oracle8i. External
LOBs store only binary data (
BFILEs). Together, internal and external
LOBs provide considerable flexibility in handling large amounts of data.
Data stored in a
LOB is called the
LOB's value. To the Oracle8i server, a
LOB's value is unstructured and cannot be queried. You must unpack and interpret a
LOB's value in cartridge-specific ways.
LOBs can be manipulated using the Oracle Call Interface (OCI) or the PL/SQL
DBMS_LOB package. You can write functions (including methods on object types that can contain
LOBs) to manipulate parts of
LOBs. Details on
LOBs can be found in the Oracle8i Application Developer's Guide - Large Objects (LOBs).