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relational model การใช้

ประโยคมือถือ
  • The relational model gathers data together using information in the data itself.
  • Maier established some of the earliest results on using the relational model.
  • For example, databases of relational model employed in almost all database systems.
  • In the relational model these are the Database Management System or DBMS.
  • Such relational models provide declarative methods for specifying data and queries.
  • The relational model, for example, defines operations such as join.
  • In the relational model, this is a runtime operation.
  • However, neither of these restrictions is part of the relational model or any SQL standard.
  • The relational model was the first database model to be described in formal mathematical terms.
  • As with the relational model, this would permit closed loop process control became theoretically possible.
  • The N1QL data model is also a proper superset and generalization of the relational model.
  • This model is transformed into a relational model, which in turn generates a relational database.
  • The concept of Null was introduced into SQL to handle missing information in the relational model.
  • The relational model employs sets of ledger-style tables, each used for a different type of entity.
  • For the relational model it is a requirement that each part of a tuple be atomic.
  • In the relational model these are the views.
  • Since DMSII supported both hierarchical and relational models, a data set could be disjointed or embedded.
  • All work after this, including the Boyce-Codd normal form method was based on this relational model.
  • Some of these extensions to the relational model integrate concepts from technologies that pre-date the relational model.
  • The most popular example of a database model is the relational model, which uses a table-based format.
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