Data Definition Language (DDL)
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- Used to specify a database scheme as a set of definitions expressed
in a DDL
- DDL statements are compiled, resulting in a set of tables stored in a
special file called a data dictionary or data directory.
- The data directory contains metadata (data about data)
- 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
- 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