Database management system with active data dictionary

• US 4,774,661 A
• Filed: 11/19/1985
• Issued: 09/27/1988
• Est. Priority Date: 11/19/1985
• Status: Expired due to Term

• Current Assignee: NCR Corporation (NCR Voyix Corporation)
• Original Assignee: AMERICAN TELEPHONE AND TELEGRAPH COMPANY, AT&T INFORMATION SYSTEMS
• Inventors: Kumpati, Murari
• Primary Examiner(s): Shaw, Gareth D.
• Assistant Examiner(s): Adams, Rebecca L.
• Application Number:
  US06/799,061
• Time in Patent Office: 1,043 Days
• Field of Search: 364/200 MS File, 364/300, 364/900 MS File
• US Class Current: 1/1
• CPC Class Codes: G06F 16/21 Design, administration or maintenance of databases
• CPC Class Codes: G06F 16/24 Querying
• CPC Class Codes: G06F 16/252 between a Database Management System and a front-end application
• CPC Class Codes: Y10S 707/99933 Query processing, i.e. searching

Abstract

This invention pertains to database management systems and, in particular, to a database management system which has an active data dictionary that the user can both access and modify. The user makes use of simple commands to control, order and query not only the underlying data controlled by the database management system but also the contents of the data dictionary. This capability enables the user to write generic application programs which are logically independent of the data since the subject database management system enables the user/application program to access all data in the database independent of each application program'"'"'s data model.

Claims

1. A database management system which runs on a computer serving a plurality of users and which interfaces a plurality of user application programs to a database for managing sets of data stored on said database comprising:

data dictionary means for specifying relationships between each of said user application programs and said sets of said data stored in said database associated with each of said user application program;

data model means for controlling the definition of the specified relationships of said data dictionary;

query means responsive to change commands from a user application program for modifying said data model;

wherein said query means includes means responsive to said change commands for changing said data dictionary to correspond to said data model changes; and

said query means further includes means responsive to a data request from said user application program for accessing the requested sets of said data from said database.

2. A database management system for interconnecting a plurality of user application programs with a database containing sets of data associated with said user application programs comprising:

data dictionary means for maintaining a list of the sets of said data associated with each of said application programs;

data model means for controlling the generation of said list by defining the logical relationships of said list;

query means responsive to change commands from a user application program for modifying said data model;

wherein said query means is additionally responsive to said change commands for changing said data dictionary to correspond to said data model changes; and

said query means further responsive to a data request from said user application program for accessing the requested sets of said data.

3. A method of modifying a database management system which runs on a computer serving a plurality of users and which interfaces a plurality of user application programs to a database for managing sets of data stored on said database having a data dictionary which specifies relationships between a plurality of user application programs and the sets of said data stored in said database associated with each of said plurality user application programs and a data model which controls the definition of said data dictionary relationships and said database management system having a query processor that allows said plurality of application programs to access and modify said database, comprising the steps of:

modifying said data model by one of said applications via said query processor;

automatically making changes by said query processor to said data dictionary to correspond to said data model modifications; and

accessing sets of said data by said one of said application programs via said query means.

4. A method of modifying a database having a data dictionary which describes the attributes of the data stored in the database, a data model which describes the characteristics of the data dictionary by defining relationships between said data dictionary and said attributes and a query processor that allows a plurality of application programs to access and modify said database, comprising the steps of:

modifying said data model by one of said plurality of application programs via query processor;

automatically making corresponding modifications to said data dictionary by said query processor in response to said data model modifications; and

accessing said data of said database by said one of said plurality of applications programs via said query processor.

5. A database management system which runs on a computer serving a plurality of users and which interfaces a plurality of user application programs to a database for managing the data stored on said database comprising:

database change processor means connected to said database;

data definition library means for maintaining a list of the ones of said data associated with each of said application programs;

wherein said database change processor means is additionally connected to said data definition library means;

database command processor means responsive to change commands from said one of said application programs for routing said change commands to said query processor means;

query processor means responsive to said change commands from said one of said user application programs for converting a data model change command to both a list change command to modify said list and a corresponding data change command to modify said data associated with said one user application program and to transfer a request to said database change processor for database locations to be modified for said list and associated data;

said database change processor means responsive to said request for identifying said locations and to transfer the identified locations to said query processor means; and

said query processor means responsive to said identified locations for modifying said associated data and said list via said database command processor means and said database change processor means.