Relational database management system

• US 5,680,614 A
• Filed: 05/20/1993
• Issued: 10/21/1997
• Est. Priority Date: 05/20/1992
• Status: Expired due to Term

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Bakuya, Takao, Matsui, Masato
• Primary Examiner(s): Black, Thomas G.
• Assistant Examiner(s): LEWIS, CHERYL RENEA
• Application Number:
  US08/063,746
• Time in Patent Office: 1,615 Days
• Field of Search: 395/500, 395/700, 395/600, 395/161, 395/159, 364/419
• US Class Current: 1/1
• CPC Class Codes: G06F 16/284 Relational databases
• CPC Class Codes: Y10S 707/99932 Access augmentation or optimizing
• CPC Class Codes: Y10S 707/99934 Query formulation, input preparation, or translation
• CPC Class Codes: Y10S 707/99943 Generating database or data structure, e.g. via user interface
• CPC Class Codes: Y10S 707/99944 Object-oriented database structure

Abstract

In a database management system of the present invention, a trigger definition means which defines activation condition an contents of a triggered operation activated upon execution of updating for a table further defines an operation where an exception is generated for an update request against the constraint given to the table, or a triggered operation based on the reference constraint given among a plurality of tables, or a triggered operation based on the relations among the system tables contained in the system directory. The trigger definition means also specifies an operation mode as a condition for execution of the triggered operation. The trigger execution means executes the triggered operation when the trigger operation mode designated by the update request and the operation mode specified in the trigger definition are the same and does not execute any trigger execution when they are not the same.

Claims

1. A relational database management system comprising:

a relational database to store a plurality of tables;

data manipulation means for updating a record in one of the tables in said database upon receipt of an update request for said record;

trigger definition means for supplying a trigger definition of an activation condition and contents of a triggered operation activated upon execution of the update request for said table, and for generating the trigger definition to cause an exception to be generated for the update request against a plurality of constraints given to said table; and

trigger execution means for activating the triggered operation according to the trigger definition given by said trigger definition means, processing the triggered operation by invoking said data manipulation means, and executing exception generation without invoking said data manipulation means for the update request if the update request violates one of the plurality of constraints given to said table according to the trigger definition generated by said trigger definition means,

wherein said data manipulation means invokes said trigger execution means when said trigger definition exists for the table when it is to be updated by the update request, and aborts update processing for the table when the exception generated is executed by said trigger execution means.

2. A relational database management system of claim 1 wherein said trigger definition means specifies a trigger operation mode as the activation condition for execution of the triggered operation, and said trigger execution means executes the triggered operation only when the trigger operation mode designated by the update request is equal to the trigger operation mode specified in the trigger definition, and said trigger execution means does not execute the triggered operation when the trigger operation mode designated by the update request and the trigger operation mode specified in the trigger definition are not equal.

3. A relational database management system of claim 1 wherein said trigger definition means defines the contents of a triggered operation based on reference constraints given for the plurality of tables defined in said database, and said trigger execution means invokes said data manipulation means and processes the triggered operation based on a one of the reference constraints generated by said trigger definition means and executes exception generation when the update request is against said one of the reference constraints.

4. A relational database management system of claim 3 wherein said trigger definition means specifies a trigger operation mode as the activation condition for execution of the triggered operation, and said trigger execution means executes the triggered operation only when the trigger operation mode designated by the update request is equal to the trigger operation mode specified in the trigger definition, and said trigger execution means does not execute the triggered operation when the trigger operation mode designated by the update request and the trigger operation mode specified in the trigger definition are not equal.

5. A relational database management system comprising:

a relational database to store a plurality of first tables;

a system directory to store as system tables information on resources including a plurality of second tables, columns and indices defined in said database, relations among said resources, and access privileges for said resources;

data manipulation means for updating of records in the plurality of first tables including addition, replacement and deletion for the plurality of first tables in said database and updating of said system directory;

trigger definition means for supplying a trigger definition of an activation condition and contents of a triggered operation activated upon execution of the update request for said table, and defining the triggered operation based on the relations stored in the system tables in said system directory;

trigger execution means for activating the triggered operation according to the trigger definition given by said trigger definition means, processing the triggered operation by invoking said data manipulation means;

resource manipulation means for processing resource manipulations; and

system directory management means for storing in the system tables a result of resource manipulation processing by said resource manipulation means by invoking said data manipulation means.

6. A relational database management system of claim 5 wherein said trigger definition means specifies a trigger operation mode as the activation condition for execution of the triggered operation, and said trigger execution means executes the triggered operation only when the trigger operation mode designated by the update request is equal to the trigger operation mode specified in the trigger definition and said trigger execution means does not execute the triggered operation when the trigger operation mode designated by the update request and the trigger operation mode specified in the trigger definition are not equal.

7. A relational database management system of claim 6 wherein said trigger definition means further defines a plurality of trigger operation modes and a triggered operation for each operation mode, and said trigger execution means executes, only when the trigger operation mode designated by the update request and the trigger operation mode specified in the trigger definition are equal, a triggered operation corresponding to said trigger operation mode selectively and said trigger execution means does not execute the triggered operation when the trigger operation mode designated by the update request and the trigger operation mode specified in the trigger definition are not equal.

8. A relational database management system of claim 5 wherein said trigger definition means generates a definition which causes an exception for an update request against a constraint given to said system tables and said trigger execution means which, based on the definition by said trigger definition means, executes exception generation without invoking said data manipulation means upon processing the update request against the constraint given to said system table.

9. A relational database management system of claim 5 wherein said trigger definition means defines the contents of a triggered operation based on reference constraints given for the plurality of second tables defined in said database, and

said trigger execution means invokes said data manipulation means and processes the triggered operation based on a reference constraint defined by said trigger definition means and executes exception generation when an update request is against said reference constraint.

10. A relational database management system of claim 5, wherein said resource manipulations include resource definition, resource deletion, privilege grant and privilege revoke.

11. A relational database management system comprising:

a relational database to store a plurality of tables;

data manipulation means for updating a record in one of the tables in said database upon receipt of an update request for said record;

trigger definition means for supplying a trigger definition of an activation condition and contents of a triggered operation activated upon execution of the update request for said table, and for defining the contents of a triggered operation based on a plurality of reference constraints given to a plurality of tables in said database; and

trigger execution means for activating the triggered operation according to the trigger definition given by said trigger definition means, processing the triggered operation by invoking said data manipulation means, wherein said trigger definition means defines the contents of a triggered operation based on reference constraints given for a plurality of tables defined in said database, and said trigger execution means invoking said data manipulation means and processing the triggered operation based on the one of the reference constraints generated by said trigger definition means and executes exception generation when the update request is against said one of the reference constraints.

12. A relational database management system of claim 11 wherein said trigger definition means specifies a trigger operation mode as the activation condition for execution of the triggered operation, and said trigger execution means executes the triggered operation only when the trigger operation mode designated by the update request is equal to the operation mode specified in the trigger definition and said trigger execution means does not execute the triggered operation when the trigger operation mode designated by the update request and the trigger operation mode specified in the trigger definition are not equal.