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*'''Status''': ''complete'' | *'''Status''': ''complete'' | ||
*'''Description''' | *'''Description''' | ||
− | :Meta-''something'' is ''something'' about '' | + | :Meta-''something'' is ''something'' about ''something'' (replace ''something'' by any name pertaining to philosophy or computer science). For instance, metadata are data that describe the structure and other properties of data (generally user data). For instance, the ''table of tables'' (generically named SYS_TABLE) in the ''catalog'' of any relational database is a metatable that contains metadata. Being said in passing, it includes a row that describes this table itself. |
:The domain of database engineering makes much use of ''meta''-level concepts. For instance any CASE tool includes some sort of database in which it stores its data. This database contains descriptions of schemas, among others. These descriptions are metadata. This database bears several names according to the community that uses it, namely ''metadatabase'', ''metabase'', ''(metadata) repository'', ''model base'' or ''encyclopedia'' (this one a bit outdated). | :The domain of database engineering makes much use of ''meta''-level concepts. For instance any CASE tool includes some sort of database in which it stores its data. This database contains descriptions of schemas, among others. These descriptions are metadata. This database bears several names according to the community that uses it, namely ''metadatabase'', ''metabase'', ''(metadata) repository'', ''model base'' or ''encyclopedia'' (this one a bit outdated). | ||
:The term ''meta-model'' designates a model that is used to describe other models. Since the database community prefers the term ''schema'' instead of ''model'' (the latter having another interpretation, as in ''relational model''), this proposition translate as follows: the term ''meta-schema'' designates a schema that is used to describe other schemas. | :The term ''meta-model'' designates a model that is used to describe other models. Since the database community prefers the term ''schema'' instead of ''model'' (the latter having another interpretation, as in ''relational model''), this proposition translate as follows: the term ''meta-schema'' designates a schema that is used to describe other schemas. |
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ER model, Individual model, Merise model, UML class diagrams, wide-spectrum model, GER model, DB-MAIN model, logical data model, temporal model, legacy data model, relational model, network model, hierarchical model, OO model, OR model, XML model, large schema layout, semantic and statistical aspects of models, IS-A relation, wrappers
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