COMPRESSION

Default: METADATA_ONLY

Purpose

Specifies which data to compress before writing to the dump file set.

Syntax and Description

COMPRESSION=[ALL | DATA_ONLY | METADATA_ONLY | NONE]

  • ALL enables compression for the entire export operation. The ALL option requires that the Oracle Advanced Compression option be enabled.

  • DATA_ONLY results in all data being written to the dump file in compressed format. The DATA_ONLY option requires that the Oracle Advanced Compression option be enabled.

  • METADATA_ONLY results in all metadata being written to the dump file in compressed format. This is the default.

  • NONE disables compression for the entire export operation.

Restrictions

  • To make full use of all these compression options, the COMPATIBLE initialization parameter must be set to at least 11.0.0.

  • The METADATA_ONLY option can be used even if the COMPATIBLE initialization parameter is set to 10.2.

  • Compression of data using ALL or DATA_ONLY is valid only in the Enterprise Edition of Oracle Database 11g or later, and they require that the Oracle Advanced Compression option be enabled.

Example

The following is an example of using the COMPRESSION parameter:

> expdp hr DIRECTORY=dpump_dir1 DUMPFILE=hr_comp.dmp COMPRESSION=METADATA_ONLY

This command will execute a schema-mode export that will compress all metadata before writing it out to the dump file, hr_comp.dmp. It defaults to a schema-mode export because no export mode is specified.

See Also:

Oracle Database Licensing Information for information about licensing requirements for the Oracle Advanced Compression option