JPH0447345A - File restoration controlling system - Google Patents

Abstract

PURPOSE:To quickly restore a file fault by holding the update history file of a master file, and controlling those by an update history number. CONSTITUTION:A restoring means 16 using the update history number accesses a generation control file 13 by the inputted update history number, for instance, 250. first of all, corresponding data is extracted by a retrieving key (in this case, Taro Yamamoto), and next, the inputted update history number and the update history number of each generation are compared with each other, and all items are shifted until the item over the inputted update history number is gone. for instance, since the update history number of the latest generation is 300, and the update history number of the item of one generation before is 223, the item of one generation before is shifted to the item of the latest generation, and the item of the update history number 300 is deleted. At that time, the corresponding bit of the null status 152 of a data area in an update history number.area control file 15 corresponding to an addres sin the deleted item is returned to a null state. Thus, the file fault can quickly be restored.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention is a method for processing a file storing a large amount of information such as personnel information in an online system (referred to as a master file) in the case where a file failure such as an update error does not occur. This invention relates to a file recovery control method that takes into consideration speeding up recovery of files.

[Conventional technology]

Conventionally, the method for updating mask files for this type of information was to directly destroy and update the corresponding data in the master file based on update instruction data, and problems such as update errors occurred in the mask file due to programming errors or operational errors. In this case, restore the mask file from the mask file storage medium that is regularly saved as a backup, and restore the mask file to the state immediately before the failure occurred using the update instruction data from the time the failure occurred. Ta.

[Problem to be solved by the invention]

The above-mentioned conventional mask file recovery method has the drawback that the master file is played back from the mask file storage medium, which requires time and effort to play back.

[Means to solve the problem]

In a file recovery control method when a file failure occurs in a system that updates data files in real time, the present invention provides a method for controlling file recovery when a file failure occurs in a system that updates data files in real time. an update history number/area management file having a block indication bit, and the update history number of the data file and the storage relative address of each data in the data file for each search key that each data stored in the data file has. (a) an update request is made by an application program of the system, and the requested update data is displayed as an empty display in the data file; (b) searching for a bit and storing it at a relative address in the data file corresponding to the first suspicious empty bit;
(c) Search the generation management file using the search key of the update data, and if there is a match, search the update generation items stored in correspondence with the search key. (d) storing the update history number and the storage relative address of the update data at the time when the update request was made in the generation management file as an item of the latest generation; Search with the search key of the update data, and if there is no match, add the search key of the update data to the generation management file, and set the update history number at the time of the update request in correspondence to the added search key. and the storage relative address of the update data in the generation management file as an item of the latest generation, and perform the processes (a) to (d) on the series of update data requested to be updated by the application program of the system. a file access management means that adds one to the update history number upon completion for all the number of items; All items by generation for each search key including the item having an update history number greater than the update history number inputted from the data input device are moved toward the latest generation while discarding the items that were in the latest generation. The shift is repeated for each generation, and the update history number/empty indication bit of the data file in the area management file corresponds to the storage relative address of the data in the item deleted from the generation management file by the shift. It consists of a recovery means by emptying the update history number.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a block diagram showing one embodiment of the present invention. In FIG. 1, this embodiment includes an application program 11, a file access management means 12, a generation management file 13, a data file 14, an update history number/area management file 15, and a recovery means 1 using update history numbers.
6 and a data input device 17.

Here, the generation management file 13, the data file 14, and the update history number/area management file 15 are mask files.

Next, the operation of this embodiment will be explained using salary management data as an example of file updating means and recovery means using update history numbers.

Figure 2 shows update instruction data 21 at the time of new registration and update instruction data 2 at the time of first update by the application program.
2, FIG. 3 shows the state of the mask file immediately after new registration, and FIG. 4 shows the state of the mask file immediately after the first update.

The latest update history number 151 in the update history number/area management file 15 in FIGS. 3 and 4 is set to "1" when the mask file is generated, and "1" is set after a series of file update processes are performed. Uploaded by 1”.

Empty status 152 of data area is data file 1
The position of the empty status bit corresponds to the relative address of the data file 14, and is "0" if the file is empty, and 1 if it is available.

Next, referring to FIG. 3, the application program 11
Now, a case where the update instruction data 21 shown in FIG. 2 is updated (newly registered) will be explained.

The file access management means 12 searches for the empty status 152 of the data area in the update history number/area management file 15 from the left, and selects the empty area of the data file 14 from the position of the first empty bit found (relative address A in FIG. 3). and write the update instruction data 21 into the empty area. Furthermore, the search key of the update instruction data 21 is registered, and the relative address A and the latest update history number 151 ("223" in FIG. 3) are written in the latest item corresponding to the search key of the generation management file 13. When the above processing is completed for a series of update instruction data inputted from the application program 11, the latest update history number 151 in the update history number/area management file 15 is incremented by 1 and the process ends.

Next, referring to FIG. 4, the application program 11
Now, a case where the update instruction data 22 shown in FIG. 2 is updated (changed) will be explained. File access management means 1
2 searches the empty status 152 of the data area in the update history number/area management file 15 from the left, secures an empty area in the data file 14 from the position of the first empty bit found (relative address B in FIG. 4), and updates it. Write the instruction data 22 into the empty area, search the generation management file 13 using the search key of the update instruction data 22 (Yamada Abe in this example), and search the items of all generations registered corresponding to the matching search key. Shift to the previous generation item, and use relative address B and latest update history number 151 (4th
When 0 or more processes for writing 0 or more of the update instruction data inputted from the application program 11 to the latest item (°゛300'' in the figure) are completed, the update history number/latest update history number 1 in the area management file 15 is completed.
Add 1 to 51 and end.

A schematic flow diagram of the above operation is shown in FIG.

Next, suppose that some kind of file failure occurs in this state, and a search key (in this case, Shiraki Taibe) and an update history number at the time of recovery, for example "250", are input from the data input device 17.

The recovery means 16 based on the update history number accesses the generation management file 13 based on the input data. First, extract the corresponding data using the search key (in this case, Shiraki Abe), then compare the input update history number with the update history number of each generation, and then search all items until there are no items with the input update history number or higher. Shift the item to the left. For example, referring to the generation management file 13 in Figure 4, the update history number of the latest generation item is "300" and the update history number of the item one generation ago is "223", so the item one generation ago is the latest generation item. Shifted to item and update history number “300”
” will be deleted. At that time, the update history number corresponding to the address in the deleted item/empty status 152 of the data area in the area management file 15
Returns the J bit to the empty state. Recovery is completed by performing the above processing on all input search keys.

〔Effect of the invention〕

As explained above, the present invention has an update history file for mask files and can manage them using update history numbers, so that the update history can be used to prevent file failures caused by program errors, operational mistakes, etc. This has the effect of quickly restoring files to any point in time using numbers.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing one embodiment of the present invention, and FIG.
The figure is a configuration diagram of update instruction data, Figure 3 is a file state diagram at the time of new registration, Figure 4 is a file state diagram at the time of modification, and Figure 5 is a file state diagram at the time of modification.
The figure is an operation flow diagram when updating a file, and FIG. 6 is an operation flow diagram when restoring a file. 11... Application program, 12... File access management means, 13... Generation management file, 14... Data file, 15... Update history number/area management file, 16... Update history number 17...Data input device, 21...Update instruction data at the time of new registration, 22...Update instruction data at the time of change,...Latest update history number,...Empty data area status.

Claims (1)

[Claims] 1. In a file recovery control method when a file failure occurs in a system that updates data files in real time, the data file, an update history number indicating the number of updates of the data file, and a relative relationship between the data file and the data file. An update history number/area management file having a vacant block indication bit for each address, and the update history number of the data file and each data in the data file for each search key that each data stored in the data file has. a generation management file that manages storage relative addresses as items for each update generation and in the order of the update generations; Search for an empty bit and store it in the relative address of the data file corresponding to the first empty bit found, (b) block the first empty bit found, and (c) store the generation management file in the data file. Search the update data using the search key, and if there is a match, shift the update generation items stored corresponding to the search key one generation earlier, and select the update history number and the update data at the time when the update request was made. (d) search the generation management file with the search key of the update data, and if there is no match, store the storage relative address of the update data in the generation management file as an item of the latest generation; Adding the search key, and storing the update history number at the time of the update request and the storage relative address of the update data in the generation management file as a latest generation item in correspondence with the added search key. , a file access management means that adds 1 to the update history number when the processes of (a) to (d) are completed for all of the series of update data requested to be updated by an application program of the system; The item having an update history number greater than the update history number input from the data input device remains until there are no more items in the generation management file that have an update history number greater than the update history number input from the data input device. All items by generation for each of the search keys containing the search keys are shifted one generation at a time toward the latest generation while discarding the items that were in the latest generation, and the items deleted from the generation management file by the shift are the update history number corresponding to the storage relative address of the data in the item;
A file recovery control method comprising a recovery means based on an update history number that empties the empty indicating bit of the data file in the area management file. 2. In the update history number recovery means, the item in the generation management file has an update history number greater than the update history number input from the data input device only with respect to the search key input from the data input device. All items by generation for each of the input search keys including the items with update history numbers greater than the input update history number are discarded while the items in the latest generation are discarded until The shift is repeated for each generation toward the latest generation, and the update history number of the data file in the area management file corresponds to the storage relative address of the data in the item deleted from the generation management file by the shift. 2. The file recovery control method according to claim 1, further comprising means for emptying said empty block indicating bit.