JPH04309145A - Data file control system - Google Patents

Abstract

PURPOSE:To shorten time required for recovering a data file. CONSTITUTION:When a work program 10 outputs a data processing request, a data processing means 20 inputs/outputs data between a data file 90 and a buffer 70 by a data input/output means 80, when the data are updated, the information is outputted to an updated data file 40, and the updated image is outputted to an updated data journal file 60. The data file 90 is saved onto a saved data file 120. When recovering the data file 90 by using the saved data file 120 and the updated data journal file 60 in the case of generating the fault at the data file 90, the updated data file 40 is read, updated block information 200 is prepared, the saved data file 120 is read and compared with the updated block information 200 at a block judging means 150 and only when the block is updated, the data file 90 is written back by a restore processing means 140.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data file control system, and more particularly to a database operation technique in an information processing system.

0002

2. Description of the Related Art As computers are widely used in society and databases are used in a wider range of applications, the reliability of database systems has become important. However, data file failures may occur due to software errors or hardware failures, and data file recovery measures are also required.

A conventional data file control system will be described with reference to FIG. and controls the data file 770. When the data file 770 is updated, the journal output means 730 writes the updated data to the updated data journal file 740.

[0004] When a failure occurs, the data file 7
70 with the saved data file 800, and in order to return the replaced data file 770 to the latest state, the updated data journal file 740 is read by the journal input means 850 according to instructions from the recovery program 830, and the data file 770 is By tracing all the updated images from the time of backup, the system is restored to the latest state.

[0005]

[Problems to be Solved by the Invention] In the conventional database technology described above, since update images performed on all blocks are traced, if the amount of updates from the time when the data file was saved increases, it becomes difficult to restore the data file. The disadvantage is that it takes a lot of time.

Accordingly, the present invention provides a data file control method that aims to improve system operability and maintainability by shortening the time required to restore data files.

[0007]

[Means for Solving the Problems] The data file control method of the present invention includes a data processing means that receives a data processing request from a business program and performs control; data input/output means that writes the contents of the block to a data file in block units; journal output means that writes the updated journal to the updated data journal file in the case of an update command; and update data that manages information in units of blocks. an update data output means for writing a file and identification information corresponding to the updated block to an update data file; a storage processing means for controlling saving the data file to a save data file on an auxiliary storage device; A block output means that outputs the contents block by block, a recovery processing means that controls recovery according to the request of the recovery program when a failure occurs in the data file, and an update data input that reads update block information from the update data file into memory. block input means for reading a block from a saved data file; block determination means for comparing the read block with updated block information to determine whether it is an updated block; and restore processing means for writing the updated block back into the data file. ,
It has a journal input means for reading an updated journal from an updated data journal file, and a journal determining means for comparing updated block information and the updated journal to determine a journal related to an updated block.

[0008]

Embodiments Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing one embodiment of the present invention. In FIG. 1, one embodiment of the present invention has a data processing means 20 that receives and controls data processing requests from a business program 10, and a data input/output means 80.
, update data output means 30 and journal output means 5
Connected to 0. The data input/output means 80 has a process of reading the contents of the data file 90 into the buffer in units of blocks and a process of writing the contents in the buffer to the data file 90 in units of blocks. The journal output means 50 writes the updated journal to the updated data journal file 60 in the case of an update command. The update data output means is connected to an update data file 40 that manages information for each block, and writes identification information corresponding to the updated block to this data file 40. The storage processing means 100 performs control to save the data file 90 to a save data file 120 on the auxiliary storage device. The block output means 110 outputs the contents of the data file 90 block by block, and outputs it to the save data file 120. The recovery processing means 100 controls recovery in response to a request from a recovery program when a failure occurs in a data file. Update data input means 210 reads update block information from update data file 40 into memory. The block input means 130 reads a block from the saved data file 120, and the block determination means 150 compares the read block with updated block information to determine whether it is an updated block. The restore processing means writes the updated block back to the data file 90. The journal input means 190 reads the updated journal from the updated data journal file 60. The journal determining means compares the updated block information and the updated journal to determine the journal related to the updated block.

Next, the operation of one embodiment of the present invention will be explained. In this embodiment, when the business program 10 issues a data processing request, control is transferred to the data processing means 20, and when data input/output is required, the data input/output means 80 performs data processing between the data file 90 and the buffer 70. Block input/output is performed. When data is updated, update block information in the form of a bitmap indicating whether each block in the data file 90 is an update block is output to the update data file 40, and the update image is stored in the post-update data journal file. Output to 60.

FIG. 2 shows data input/output in the case of data update.
This shows the relationship between update data output and post-update journal output, and FIG. 3 is a flowchart showing data processing.

The data file 90 is saved by the save processing means 100, and the block output means 110 stores the data in the save data file 120. A failure occurs in the data file 90, and the evacuation data file 12
0 and the updated data journal file 40, the update data input means 210 reads the update data file 40, creates update block information 200 on memory, and the block input means 130 reads the updated data file 120. The block determining means 150 compares the updated block information 200 with the updated block information 200, and the restore processing means 140 writes back to the data file 90 only if the block is an updated block.

FIG. 5 shows a detailed processing flow of the block determining means 150. The journal input means 190 reads the journal from the updated data journal file 60, the journal judgment means 180 compares it with the updated block information, and transfers control to the recovery processing means 170 to perform recovery processing only if the journal is related to the updated block data. I do. FIG. 6 shows a detailed processing flow of the journal determining means 180. Recovery is completed when all post-update journals have been read. FIG. 4 shows the flow of recovery processing.

[0014]

[Effects of the Invention] The present invention relates to database technology for information processing systems, and even if there are many data updates from the time the data file was evacuated, only the blocks that were being updated at the time of failure are subject to recovery. In order to
It becomes possible to shorten the time required to restore data files, and it is possible to obtain the effect of preventing a decline in system operability and maintainability.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an embodiment of the present invention.

FIG. 2 is a diagram showing the relationship between data input/output, update data output, and post-update journal output in the case of data update.

FIG. 3 is a diagram showing the flow of data processing.

FIG. 4 is a diagram showing a flow of recovery processing.

FIG. 5 is a diagram showing a processing flow of block determining means.

FIG. 6 is a diagram showing a processing flow of journal determining means.

FIG. 7 is a diagram showing a conventional data file control method.

[Explanation of symbols]

10 Business program 20 Data processing means 30 Update data output means 40 Update data file 50 Journal output means 60 Updated data journal file 70
Buffer 80 Data input/output means 90 Data file 100 Save processing means 110 Block output means 120 Saved data file 130 Block input means 140 Restore processing means 150 Block judgment means 160 Recovery program 170 Recovery processing means 180 Journal judgment means 190 Journal input means 200 Update Block information 210 Update data input means

Claims (1)

[Claims] Claim 1: A data processing means that receives and processes data processing requests from a business program, a data input/output device that reads the contents of a data file into a buffer in blocks, and writes the contents of the buffer to a data file in blocks. a journal output means for writing updated data to an updated data journal file when data is updated; an updated data file that manages information on a block-by-block basis; and an identification corresponding to the updated block. An update data output means for writing information to an update data file, a storage processing means for controlling to save the data file to an evacuation data file on an auxiliary storage device, and a block output means for outputting the contents of the data file in blocks. a recovery processing means for controlling recovery in response to a request from a recovery program when a failure occurs in the data file; and an update data input means for reading update block information from the update data file into memory;
A block input means for reading a block from a saved data file, a block judgment means for comparing the read block and updated block information, a restore means for writing saved data of an updated block to a data file, and an updated journal from an updated data journal file. 1. A data file control method characterized by comprising a journal input means for reading a journal, and a journal judgment means for comparing updated block information with an updated journal, and is characterized by high-speed recovery in the event of a failure.