Method and apparatus for caching and reusing object identifiers

• US 6,662,191 B1
• Filed: 12/21/2000
• Issued: 12/09/2003
• Est. Priority Date: 12/21/2000
• Status: Active Grant

• Current Assignee: Amdocs Development Limited (Amdocs Ltd.), Amdocs Software Systems Limited (Amdocs Ltd.)
• Original Assignee: Amdocs Software Systems Limited (Amdocs Ltd.)
• Inventors: Gustafson, Michael A., Kota, Rao S., Cherniavsky, John P.
• Primary Examiner(s): JUNG, DAVID YIUK
• Application Number:
  US09/745,903
• Time in Patent Office: 1,083 Days
• Field of Search: 707/1-206, 709/310-320, 717/100-119
• US Class Current: 1/1
• CPC Class Codes: G06F 16/2272 Management thereof
• CPC Class Codes: G06F 16/27 Replication, distribution or synchronisation of data between databases or within a distributed database system; Distributed database system architectures therefor
• 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
• CPC Class Codes: Y10S 707/99946 Object-oriented database structure network
• CPC Class Codes: Y10S 707/99952 Coherency, e.g. same view to multiple users

Abstract

A method and system is provided for distributing and reusing object identifiers in a distributed database system. A first table of object identifiers created by the database is maintained for supplying unallocated object identifiers for each type. A second table of object identifiers is also maintained containing reusable and distributable object identifiers to one or more application server in the database system. The application server obtains a predetermined number of object identifiers from the first and second tables to be stored in each of the application servers for servicing client applications related to the application server.

Claims

1. A method for maintaining object identifiers in a distributed database system, the distributed database having at least one application server independently located from each other, the application servers requiring the object identifiers of a plurality of types for servicing client applications, the method comprising:

maintaining a first source of object identifiers created by the database system for supplying unallocated object identifiers;

maintaining a second source of object identifiers including reusable object identifiers;

storing a predetermined number of object identifiers in memory coupled to the application server for fulfilling a request by a client application, the request containing a requested number of object identifiers of a plurality of data types;

if the application server can not distribute the requested number of object identifiers, requesting additional object identifiers from the second source;

if the second source can not fulfill the request of the application server, requesting additional object identifiers from the first source,

wherein an additional number of the object identifiers of each type are requested from the first and second source by the application server when the application server assigns the stored object identifiers, and wherein the additional number of the object identifiers increases by a predetermined factor each time a request is made, such that the object identifiers may be maintained in the distributive database system.

2. The method of claim 1 wherein the first source identifies the last created object identifier of each type.

3. The method of claim 1 wherein the second source contains discrete blocks of object identifiers of each type.

4. The method of claim 1 wherein the step of storing further includes querying the second source for availability of the object identifiers.

5. The method of claim 1 wherein the step of storing further includes obtaining available object identifiers from the second source and the first source if the number of object identifiers provided by the second source is not sufficient to fulfill the requested number of client identifiers.

6. The method of claim 1 wherein the step of storing further includes obtaining the object identifiers directly from the first source if at least one type of the needed object identifier is not available in the second source.

7. The method of claim 1 wherein the application server obtains the needed object identifiers from the second source if there is an excessive supply of the object identifiers of such type.

8. An apparatus for distributing and reusing object identifiers in a distributed database system, the object identifiers having a plurality of types, the system comprising:

a first table of unallocated object identifiers of each data type created by the database system;

a second table of reusable object identifiers distributable to at least one application server, wherein the second table is a preferred source from which to obtain the object identifiers over the first table; and

a storage device in the application server for storing and distributing a predetermined set of object identifiers obtained from the first and second tables for servicing client applications related to the application server, wherein the storage device includes a means for requesting the object identifiers from the first table if they can not be obtained from the second table, and wherein the additional number of object identifiers increases by a predetermined rate each time the application server requests the object identifiers from the first table.

9. The system of claim 8 wherein the first table identifies the last created object identifier for each type of object identifier.

10. The system of claim 8 wherein the second table contains discrete blocks of object identifiers for each type of data.

11. The system of claim 8 wherein the storage device further includes a means for querying the second table for availability of the object identifiers requested by the client applications.

12. The system of claim 8 further comprising a means for returning unassigned object identifiers to the second table when the application server is terminated in a normal operation.

13. A method for efficiently providing object identifiers in a computer system, the method comprising:

determining if a needed object identifier is available from a first source of object identifiers, wherein the first source stores a plurality of reusable object identifiers;

accessing the first source for the needed object identifier if the needed object identifier is available from the first source; and

accessing a second source for the needed object identifier if the needed object identifier is not available from the first source, wherein the second source stores a plurality of new object identifiers.