Data Definition Language (DDL)

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Data Definition Language (DDL)

  1. Used to specify a database scheme as a set of definitions expressed in a DDL
  2. DDL statements are compiled, resulting in a set of tables stored in a special file called a data dictionary or data directory.

  3. The data directory contains metadata (data about data)
  4. The storage structure and access methods used by the database system are specified by a set of definitions in a special type of DDL called a data storage and definition language

  5. basic idea: hide implementation details of the database schemes from the users

Page created and maintained by Osmar R. Zaï ane
Last Update: Sun Sep 10 16:58:49 PDT 1995