Database-rearranging program, database-rearranging method, and database-rearranging apparatus

• US 20050246385A1
• Filed: 11/16/2004
• Published: 11/03/2005
• Est. Priority Date: 04/28/2004
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Nishino, Mitsuhide, Enbutsu, Hisayuki
• Granted Patent: US 7,949,632 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 11/1466 to make the backup process non-disruptive
• CPC Class Codes: G06F 16/2282 Tablespace storage structures; Management thereof

Abstract

A database-rearranging program which is capable of rearranging a database while maintaining high reliability, without stopping services provided by the database. When a request for rearranging the copy source database is input, a record copying module sequentially selects pages in the copy source database, and the records in the selected page are copied to the copy destination database. Further, the record copying module sets a progress of copying of each page of the copy source database to a page status management table. Thereafter, when a request for writing updated records is input, a record writing module refers to the page status management table, and when a page of the copy source database in which the updated records should be written is in an uncopied status, the updated records are written in the page of the copy source database, and when the same is in a copied status, the updated records are written in the copy source database and the copy destination database.

Claims

1. A database-rearranging program for causing a computer to carry out a process for rearranging a database in which records to be stored are defined for each of a plurality of pages, wherein the computer is caused to function as:

record copying means responsive to a request for rearranging a copy source database, for sequentially selecting pages of the copy source database, copying records in a selected one of the pages to a copy destination database, and setting a status of progress of copying of each page of the copy source database to a page status management table; and

record writing means responsive to a request for writing an updated record, for referring to the page status management table, and writing the updated record in a corresponding one of the pages of the copy source database if the page of the copy source database in which the updated record should be written is in an uncopied status, and writing the updated record in the copy source database and the copy destination database if the page in which the updated data should be written is in a copied status.

2. The database-rearranging program according to claim 1, wherein when the computer is caused to function as the record writing means, if the page in which the updated data should be written is in a being-copied status, the computer is caused to wait until the status of the page is changed to the copied status, and when the status is changed from the being-copied status to the copied status, the computer is caused to write the updated record in the copy source database and the copy destination database.

3. The database-rearranging program according to claim 1, wherein when the computer is caused to function as the record copying means, upon reception of the request for rearranging the database, the status of each of all the pages is set to the uncopied status in the page status management table, where after when copying of a page is started, a status of the page is changed to the being-copied status, and when copying of the page is completed, the status of the page is set to the copied status.

4. The database-rearranging program according to claim 1, wherein the copy source database includes a plurality of prime pages for which numbers of records to be stored therein are defined in advance, and a plurality of overflow pages for storing records which cannot be stored in the prime pages associated therewith, and

wherein when the computer is caused to function as the record copying means, the prime pages are sequentially selected, and copying processing is carried out on a selected one of the prime pages and an associated one of the overflow pages storing records which cannot be stored in the selected prime page.

5. The database-rearranging program according to claim 4, wherein when the computer is caused to function as the record copying means, copying processing of the selected prime page and copying processing of the overflow page storing records which cannot be stored in the selected prime page are executed in a same transaction.

6. The database-rearranging program according to claim 4, wherein when the computer is caused to function as the record copying means, upon selection of the prime page, the status of the selected prime page is changed to the being-copied status, and when copying processing of the selected prime page and copying of the overflow page storing records which cannot be stored in the selected prime page are both completed, the status of the selected prime page is changed to the copied status.

7. A method of rearranging a database in which records to be stored are defined for each of a plurality of pages, comprising:

a record copying step of, in response to a request for rearranging a copy source database, sequentially selecting pages of the copy source database, copying records in a selected one of the pages to a copy destination database, and setting a status of progress of copying of each page of the copy source database to a page status management table; and

a record writing step of, in response to a request for writing an updated record, referring to the page status management table, and writing the updated record in a corresponding one of the pages of the copy source database if the page of the copy source database in which the updated record should be written is in an uncopied status, and writing the updated record in the copy source database and the copy destination database if the page in which the updated data should be written is in a copied status.

8. A database-rearranging apparatus for rearranging a database in which records to be stored are defined for each of a plurality of pages, comprising:

record copying means responsive to a request for rearranging a copy source database, for sequentially selecting pages of the copy source database, copying records in a selected one of the pages to a copy destination database, and setting a status of progress of copying of each page of the copy source database to a page status management table; and

record writing means responsive to a request for writing an updated record, for referring to the page status management table, and writing the updated record in a corresponding one of the pages of the copy source database if the pare of the copy source database in which the updated record should be written is in an uncopied status, and writing the updated record in the copy source database and the copy destination database if the page in which the updated data should be written is in a copied status.

9. A computer-readable recording medium storing a database-rearranging program for causing a computer to carry out a process for rearranging a database in which records to be stored are defined for each of a plurality of pages, wherein the computer is caused to function as:

record copying means responsive to a request for rearranging a copy source database, for sequentially selecting pages of the copy source database, copying records in a selected one of the pages to a copy destination database, and setting a status of progress of copying of each page of the copy source database to a page status management table; and

record writing means responsive to a request for writing an updated record, for referring to the page status management table, and writing the updated record in a corresponding one of the pages of the copy source database if the page of the copy source database in which the updated record should be written is in an uncopied status, and writing the updated record in the copy source database and the copy destination database if the page in which the updated data should be written is in a copied status.