Distributed data base access request processing system

• US 5,046,002 A
• Filed: 04/26/1990
• Issued: 09/03/1991
• Est. Priority Date: 12/01/1986
• Status: Expired due to Term

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Ishikawa, Hiromichi, Takashi, Rinichi
• Primary Examiner(s): MacDonald, Allen R.
• Assistant Examiner(s): Ray, Gopal C.
• Application Number:
  US07/515,364
• Time in Patent Office: 495 Days
• Field of Search: 364/200 MS File, 364/900 MS File, 364/187, 364/401, 364/408, 902/40
• US Class Current: 1/1
• CPC Class Codes: G06F 16/24532 of parallel queries
• 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: G06F 16/275 Synchronous replication
• CPC Class Codes: Y10S 707/99938 Concurrency, e.g. lock management in shared database
• CPC Class Codes: Y10S 707/99939 Privileged access

Abstract

A distributed data base access request processing system in a distributed data base system including a computer system having a data base and a plurality of computer system effecting an update or a reference to the data base. A client side requesting a data base access issues a request for a synchronous processing to a server side if the data base access is related to a reference operation; whereas an asynchronous processing is requested if the data base access is associated with an update operation. On receiving such a request of a synchronous processing, the server side returns a response to the client side after the requested data base processing is completed. If an asynchronous processing is requested, the response is returned to the client side without waiting for the completion of the requested data base processing.

Claims

1. A distributed data base system including a server side system having a data base and a client side system in communication with the server side system for a client requesting access to the data base, comprising:

a client processing means for analyzing the client requesting of access including means for distinguishably coding a reference access request and an update access request, respectively, and for sending coded access requests and receiving responses to and from the server side system;

a server accept processing means for receiving and distinguishing reference access requests and update access requests and including means for responding to the client side system; and

,

a server data base processing means for processing a reference access and an update access to the data base, and wherein the server accept processing means includes response means for responding to the client side system upon receipt of the update access request prior to completion by the server data base processing means of the update access to the data base, for overlapping processing by the client processing means and the server data base processing means.

2. The system as defined in claim 1 further including means for wait processing in the server data base processing means upon receipt of an other access request by the client until completion of processing of the update access request.

3. The system as defined in claim 2 including means for end judge processing of wait processing by the data base processing means.

4. A distributed data base access request processing system having a client side system and a server side system having parallel processing by the client side system and the server side system comprising:

means for selectively coding a reference access request and an update access request by the client side system to the server side system;

means for processing the update access request in the server side system; and

,

means for accepting and decoding the reference access request and the update access request by the server side system and including means for responding to the client side system before completion of processing of the update access request wherein the client side system may process a next request parallelly with the processing of the update access request by the server side system.

5. The system as defined in claim 4 wherein the reference access request by the client side system comprises a synchronous processing request and the update access request comprises an asynchronous processing request.

6. The system defined in claim 4 further comprising:

determination means for determining whether update processing of a data base is being executed;

execution means for executing data base access processing if the update processing is complete; and

,

initiation means for initiating a wait processing to wait for completion of the update processing if the update processing is not complete.

7. A method for parallel processing by a client side system and a server side system in a distributed data base access request system comprising:

selectively coding for distinguishment requests comprising an update access request and a reference access request by the client side system to the server side system;

processing the requests in the server side system;

first responding by the server side system to the client side system after completion of the processing of the reference access request;

second responding by the server side system to the client side system before completion of processing of the update access request wherein the client side system may process and code a next request during the processing of the update access request by the server side system.

8. The method as defined in claim 7 further including waiting in the server side system for completion of processing of the update access request before processing of the next request.