Oracle Essentials [Electronic resources] : Oracle Database 10g, 3rd Edition نسخه متنی

9.7 The Metadata Challenge

On the one hand,
metadataor
descriptive data about datais incredibly important. Virtually
all types of interactions with a database require the use of
metadata, from datatypes of the data to business meaning and history
of data fields.

On the other hand, metadata is useful only if the tools and clients
who wish to use it can leverage it. One of the great challenges is to
create a set of common metadata definitions that allows tools and
databases from different vendors to interact.

There have been a number of attempts to reach an agreement on common
metadata definitions. In 2000, a standard was ratified that defines a
common interface for interchange of
metadata implementations. Named
the Common Warehouse
Metadata Interchange (CWMI) by the Object Management Group (OMG),
this standard is based on XML interchange. Oracle was one
of the early proponents and developers of the technology in this
standard. Oracle has a CWM bridge for exchanging metadata stored in
the Oracle Warehouse Builder repository. OWB also includes a metadata
viewer for more detailed metadata reports, and a viewer for data
lineage and impact analysis diagrams.