data dictionary

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data dictionary

[′dad·ə ‚dik·shə‚ner·ē]
(computer science)
A catalog which contains the names and structures of all data types.

data dictionary

A data structure that stores meta-data, i.e. data about data. The term "data dictionary" has several uses.

Most generally it is a set of data descriptions that can be shared by several applications.

Usually it means a table in a database that stores the names, field types, length, and other characteristics of the fields in the database tables.

An active data dictionary is automatically updated as changes occur in the database. A passive data dictionary must be manually updated.

In a DBMS, this functionality is performed by the system catalog. The data dictionary is a more general software utility used by designers, users, and administrators for information resource management.

The data dictionary may maintain information on system hardware, software, documentation, users, and other aspects.

Data dictionaries are also used to document the database design process itself and can accumulate meta-data ready to feed into the system catalog.

data dictionary

A database about data and databases. A data dictionary holds the name, type, range of values, source and authorization for access for each data element in the organization's files and databases. It also indicates which application programs use that data so that when a change in a data structure is contemplated, a list of affected programs can be generated.

The data dictionary may be a stand-alone system or an integral part of the DBMS. Data integrity and accuracy is better ensured in the latter case. See DBMS and data administration.
References in periodicals archive ?
REEL NT software also provides a mirrored catalog, or a duplicate copy of the data directory in a different location, so IT managers can quickly identify and recover mission-critical files if a central server is down.
5 also incorporates new built-in functions that enable web developers to manipulate files in the script directory, transfer files between the script directory and the data directory and easily move files around the server.
These include scaleability to meet changing business needs, graphical design and construction for easy and consistent development, and an open meta data directory to manage data warehouse or mart initiatives.
announced today that it has opened its meta data directory to exchange data with repositories from PLATINUM technology, inc.