Database system, its control method, and information processing apparatus

• US 7,359,925 B2
• Filed: 09/28/1998
• Issued: 04/15/2008
• Est. Priority Date: 09/30/1997
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Sugiyama, Mitsumasa
• Primary Examiner(s): Colbert; Ella
• Application Number:
  US09/161,401
• Publication Number:
  US 20020083084A1
• Time in Patent Office: 3,487 Days
• Field of Search: 707201-204, 707500-511, 707/1, 707/200, 715/500.1, 715/501, 715/502, 715503-511, 715/500, 711/162, 711/163, 711/114, 711/100, 714/6, 714/100
• US Class Current: 707/647
• 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 707/99952 Coherency, e.g. same view to multiple users
• CPC Class Codes: Y10S 707/99953 Recoverability
• CPC Class Codes: Y10S 707/99955 Archiving or backup

Abstract

A database client which can access a plurality of databases copies data selected from a source database to a destination database. The database client compares attribute items of attribute information appended to the data to be copied with those which can be set in the destination database, and directly copies an attribute item which can be set in the destination database to the corresponding attribute item. On the other hand, the database client copies attribute information of an attribute item which cannot be set in the destination database to a predetermined attribute item in the destination database. In this way, upon copying data between databases with different kinds of attribute information that can be set, the destination database can hold the attribute information of the source data.

Claims

1. An information processing apparatus which can access a plurality of databases, comprising:

first copying means for copying data selected from a first database to a second database;

determination means for determining if each of attribute items of attribute information appended to the copied data corresponds to each of attribute items of the second database; and

second copying means for copying content data of an attribute item as content data of a corresponding attribute item of the second database if it is determined by said determination means that the attribute item corresponds to one of the attribute items of the second database, and for copying content data of an attribute item and item information indicating the attribute item as content data of a predetermined attribute item of the second database in a predetermined format if it is determined by said determination means that the attribute item does not correspond to any of the attribute items of the second database, wherein said predetermined format indicates information of a mismatching attribute item.

2. The apparatus according to claim 1, wherein the predetermined format indicates an attribute item name and content.

3. The apparatus according to claim 2, further comprising information recovery means for, when content data stored in the predetermined attribute item in the predetermined format is detected, recovering the detected content data on the basis of the attribute item name and content indicated by the information.

4. The apparatus according to claim 1, further comprising:

holding means for holding conversion information indicating a correspondence between attribute items of the first and second databases, and

wherein said determination means determines based on the conversion information if each of the attribute items of the attribute information appended to the data corresponds to each of the attribute items of the second database.

5. An information processing method which can access a plurality of databases, comprising the steps of:

copying data in a first copying step selected from a first database to a second database;

determining in a determination step if each of attribute items of attribute information appended to the copied data corresponds to each of the attribute items of the second database; and

copying in a second copying step data of an attribute item as content data of a corresponding attribute item of the second database if it is determined by said determination means that the attribute item corresponds to one of the attribute items of the second database, and copying content data of an attribute item and item information indicating the attribute item as content data of a predetermined attribute item of the second database in a predetermined format if it is determined by said determination means that the attribute item does not correspond to any of the attribute items of the second database, wherein said predetermined format indicates information of a mismatching attribute item.

6. The method according to claim 5, wherein the predetermined format indicates an attribute item name and content.

7. The method according to claim 6, further comprising the information recovery step of recovering the detected content data on the basis of the attribute item name and content thereof indicated by attribute information, when content data stored in the predetermined attribute item in the predetermined format is detected in the second copying step.

8. The method according to claim 5, further comprising the step of:

a holding step of holding conversion information indicating a correspondence between attribute items of the first and second databases,

wherein the determination step includes the step of determining based on the conversion information if each of the attribute items of the attribute information appended to the data corresponds to each of the attribute items of the second database.

9. A database system which can copy data between a plurality of databases, comprising:

first copying means for copying data selected from a first database to a second database;

determination means for determining if each of attribute items of attribute information appended to the copied data corresponds to each of attribute items of the second database; and

second copying means for copying content data of an attribute item as content data of a corresponding attribute item of the second database if it is determined by said determination means that the attribute item corresponds to one of the attribute items of the second database, and copying content data of an attribute item and item information indicating the attribute item as content data of a predetermined attribute item of the second database in a predetermined format if it is determined by said determination means that the attribute item does not correspond to any of the attribute items of the second database, wherein said predetermined format indicates information of a mismatching attribute item.

10. A method of controlling a database system which can copy data between a plurality of databases, comprising the steps of:

copying data in a first copying step selected from a first database to a second database;

determining in a determination step if each of attribute items of attribute information appended to the data corresponds to each of attribute items of the second database; and

copying in a second copying step content data of an attribute item as content data of a corresponding attribute item of the second database if it is determined by said determination step that the attribute corresponds to one of the attribute items of the second database, and copying content data of an attribute item and item information indicating the attribute item as content data of a predetermined attribute item of the second database in a predetermined format if it is determined by said determination step that the attribute item does not correspond to any of the attribute items of the second database, wherein said predetermined format indicates information of a mismatching attribute item.

11. A computer-readable storage medium which stores a computer-executable control program for a database client which copies data between a plurality of databases, said control program comprising:

code for a first copying step of copying data selected from a first database to a second database;

code for a determination step of determining if each of attribute items of attribute information appended to the copied data corresponds to each of the attribute items of the second database; and

code for a second copying step of copying content data of an attribute item as content data of a corresponding attribute item of the second database if it is determined by said determination means that the attribute item corresponds to one of the attribute items of the second database, and copying content data of an attribute item and item information indicating the attribute item as content data of a predetermined attribute item of the second database in a predetermined format if it is determined by said determination means that the attribute item does not correspond to any of the attribute items of the second database, wherein said predetermined format indicates information of a mismatching attribute item.