data dictionary

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

data dictionary

(database)A data structure that stores meta-data, i.e. dataabout data. The term "data dictionary" has several uses.

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

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

An active data dictionary is automatically updated as changesoccur in the database. A passive data dictionary must bemanually updated.

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

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

Data dictionaries are also used to document the databasedesign process itself and can accumulate meta-dataready 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.

单词	data dictionary
释义	data dictionary data dictionary n (Computer Science) computing an index of data held in a database and used to assist in the access to data. Also called: data directory data dictionary data dictionary [′dad·ə ‚dik·shə‚ner·ē] (computer science) A catalog which contains the names and structures of all data types. data dictionary (database)A data structure that stores meta-data, i.e. dataabout data. The term "data dictionary" has several uses. Most generally it is a set of data descriptions thatcan be shared by several applications. Usually it means a table in a database that stores thenames, field types, length, and other characteristics ofthe fields in the database tables. An active data dictionary is automatically updated as changesoccur in the database. A passive data dictionary must bemanually updated. In a DBMS, this functionality is performed by the system catalog. The data dictionary is a more general softwareutility used by designers, users, and administrators forinformation resource management. The data dictionary may maintain information on systemhardware, software, documentation, users, and other aspects. Data dictionaries are also used to document the databasedesign process itself and can accumulate meta-dataready 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. data dictionary da·ta dic·tion·a·ry (dā'tă dik'shŭn-ār-ē) A set of standardized definitions of all data elements collected in a given health care facility. See DD See DDICThesaurusSeemetadata
随便看	benign neonatal seizures benign neoplasm benign neoplasms benign nephrosclerosis benign nocturnal childhood occipital epilepsy benign non-familial neonatal convulsions benign non-familial neonatal seizues benign occipital epilepsy benign osteoblastoma benign paediatric heart murmur benign papillary mesothelioma benign paralogia benign paroxysmal peritonitis benign paroxysmal positional nystagmus benign paroxysmal positional vertigo benign paroxysmal positional vertigo of the horizontal semicircular canal benign paroxysmal positioning vertigo benign paroxysmal postural vertigo benign paroxysmal torticollis of infancy benign paroxysmal vertigo benign paroxystic positional vertigo benign partial epilepsy benign partial epilepsy in infancy benign partial epilepsy of childhood benign partial seizures of adolescence

data dictionary

data dictionary

data dictionary

data dictionary

data dictionary

data dictionary

data dictionary

da·ta dic·tion·a·ry