Technique for providing a universal query for multiple different databases

• US 6,233,584 B1
• Filed: 09/09/1997
• Issued: 05/15/2001
• Est. Priority Date: 09/09/1997
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Purcell, Keith J.
• Primary Examiner(s): Black, Thomas
• Assistant Examiner(s): RONES, CHARLES
• Application Number:
  US08/926,063
• Time in Patent Office: 1,344 Days
• Field of Search: 707/1, 707/2, 707/3, 707/4, 707/5, 707/102, 707/103, 707/10, 707/501, 707/104, 395/701, 705/10, 705/27, 705/28, 717/2, 709/316, 709/200, 709/250
• US Class Current: 707/769
• CPC Class Codes: G06F 16/2471 Distributed queries
• CPC Class Codes: G06Q 10/087 Inventory or stock management, e.g. order filling, procurement or balancing against orders
• CPC Class Codes: Y10S 707/959 Network
• CPC Class Codes: Y10S 707/99933 Query processing, i.e. searching
• CPC Class Codes: Y10S 707/99944 Object-oriented database structure

Abstract

A technique for permitting a client in a client/server computing environment to query a plurality of databases for desired data utilizing a single query sent over a network one time. The single query need not be written in the syntax for the target database, but includes the names of the database and table within the database which contains the desired data. The query is sent from the client over the network via a specified socket, and is received by servers connected to the network which are listening to the specified socket. Each server includes code which determines if the desired data is present in a database which is associated therewith. If so, the server code generates an appropriate query for its associated database, retrieves the desired data from the database and forwards the data to the client over the network. If the data is not present in the associated database, the server preferably informs the client that the data is not present in its associated database, and the client makes a record of the responses from the servers.

Claims

1. In a computing environment having a plurality of databases and servers, each of said databases being accessible through a server associated therewith, computer readable-code for accessing data from one of the databases, comprising:

first subprocesses for generating, at a requesting entity, a single database query requesting desired data;

second subprocesses for sending the single database query in its original form over a network;

third subprocesses for permitting at least some of the servers to receive the single database query in its original form;

fourth subprocesses for determining, for each combination of the databases and the server associated therewith which received the single database query, whether the database contains the desired data, wherein each of the servers is associated with a factory class which receives the single database query and determines whether the desired data resides in the database associated with the server with which the factory class is associated; and

for the database found to contain the desired data, if any, fifth subprocesses for retrieving the desired data from the database and sending the desired data as required by the requesting entity.

2. Computer readable code for accessing data according to claim 1, wherein the requesting entity is a client and said fifth subprocesses further sends the desired data to the client.

3. Computer readable code for accessing data according to claim 1, wherein the single database query generated by said first processes is an SQL query which includes names of a target database and a table in the target database containing the desired data, but is not in a syntax required by the target database, and wherein said fifth subprocesses further generates a query for the target database containing the desired data in the proper syntactic form for the target database.

4. Computer readable code for accessing data according to claim 3, wherein said fifth subprocesses includes a factory class which generates the query for the target database.

5. Computer readable code for accessing data according to claim 1, wherein the network utilizes client/server TCP/IP socket communications, wherein said second subprocesses further comprises sending the single database query over a predefined socket port, and wherein the servers which receive the single database query in said third subprocesses are listening to the predefined socket port over the network.

6. Computer readable code according to claim 1, wherein each of the databases is a different database management system.

7. A system for accessing data in a computer environment comprising non-homogeneous databases utilizing a database query sent once from a client which is seeking data, comprising:

a plurality of servers connected via a network;

a plurality of databases, each of said databases associated with one of said servers, wherein at least one of said databases utilizes a query format which is different from the query format of others of said databases;

means associated with a client for generating a first database query requesting desired data and sending the first database query without modification thereof to said servers via the network;

a factory class associated with each of said servers for determining if the database associated with the server includes the desired data, and if so, preparing a second database query which requests the desired data in a form acceptable to the associated database having the desired data; and

means for sending the desired data from the database having the desired data to the client.

8. A system for accessing data according to claim 7, wherein said determining means further comprises preparing and sending a response to the client if said determining means determines that the associated database does not contain the desired data, the response informing the client that the database does not contain the desired data.

9. A system for accessing data according to claim 8, wherein the client constructs a record relative to the first database query in which the response from each of said databases is logged.

10. A system for accessing data according to claim 7, wherein the network utilizes client/server TCP/IP socket communications, and the client sends the first database query over the network via a predefined Java socket port, and wherein said servers which receive the first database query are programmed to listen to the predefined Java socket port.