JPH04305742A - Version management processing system - Google Patents

Abstract

PURPOSE:To execute batch processing without interrupting on-line processing and to rapidly execute the on-line processing by registering the unupdated contents of an updating part together with updating time. CONSTITUTION:When block updating is requested by the on-line processing of a user program 101, a version management part 102 requests a block corresponding to a block discriminator applied from the program 101 to a data access control part 105 and reads out the block from a data base storing area 106. Then the unupdated contents of an updating part are extracted from the read block, the extracted unupdated contents and current time information requested and acquired from an updating time managing part 104 are registered in an updating item registering area 103 as a pair of updating information and the updated block is rewritten in the area 106 by the control part 105. Thereby the batch processing can overwrite the updating information on the block contents of the area 106 to refer it and the on-line processing can refer the up-to-date block contents.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a database version control processing method, and in particular, online processing that refers to or updates the latest database contents in real time, and refers to database contents at a specific time in order to obtain statistical information, etc. The present invention relates to a version control processing method that allows online processing and batch processing to be performed simultaneously in a database processing system in which batch processing is performed on the same database.

0002

[Background Art] In order to perform batch processing to obtain statistical information, etc. at a specific time for a database that is frequently updated through online processing, generally the online processing is temporarily stopped and the contents of the database are changed during the batch processing period. There was a problem in that it caused a decline in online processing services.

[0003] As a method to solve this problem, a version control method was developed in Japanese Patent Application Laid-Open No. 57-1991 that allows online processing and batch processing to be performed simultaneously on the same database.
-141766 in detail. In this method, a database storage area and an update item registration area are provided in a secondary storage device, and a database for performing batch processing is stored in the database storage area. Further, when online processing updates the database, the updated contents are registered in the update item registration area instead of directly updating the database storage area. When referring to a block in the database through online processing, the latest contents of the block are generated by overwriting the contents of the block read from the database storage area with the updated contents of the block registered in the update item registration area. . On the other hand, when referring to a database by batch processing, the old contents before being updated by online processing can always be obtained by referring to the database storage area. In other words, 1 of the database
It is possible to simultaneously generate two contents before and after an update by online processing for one block, and online processing and batch processing can be performed simultaneously on the same database.

0004

[Problems to be Solved by the Invention] In the conventional method described above, the database contents that can be referred to by batch processing are limited to those that are stored in advance in the database storage area, and the database contents that can be referred to by batch processing are limited to those that are stored in advance in the database storage area. In order to perform batch processing on a database, it is necessary to temporarily stop online processing at that time and overwrite the contents of the update item registration area that have been registered up to that point in the database storage area, which reduces the service of online processing. There was the problem of inviting Furthermore, since the update item registration area holds the latest database contents obtained through online processing, it needs to be provided in a non-volatile secondary storage device such as a magnetic disk. When referring to a block in the database during online processing, the block is first read from the database storage area, and then the update contents related to the block are read from the update item registration area, so secondary storage is slower than the main unit. There is a problem in that the device must be accessed multiple times, reducing the real-time performance of online processing.

[0005] An object of the present invention is to update the database by online processing directly to the database storage area, and register the contents of the updated part before the update in the update item registration area together with the update time, so that the online processing can be performed. batch processing can be performed on a database at any given time without interrupting online processing.
Furthermore, the purpose of online processing is to improve the serviceability and real-time performance of online processing by making it possible to refer to the latest database by accessing only the database storage area.

[0006]

[Means for Solving the Problems] In order to solve the problems described above, in the present invention, as will be described later with reference to FIG.
An update item registration area 103 is located in the main unit, and the main unit includes a data access control unit 105 that reads or writes blocks to the database storage area, and an update time management unit that manages update times of blocks by user programs. 104, and a version management unit 102 that registers update information in an update item registration area and overwrites update information on block contents read from a database storage area, and the version management unit blocks blocks in online processing by a user program. When requested to update the block, the data access control unit reads the block from the database storage area, and stores the pre-update content of the updated part and the update time given by the update time management unit as a set of update information in the update item registration area. By registering the updated block in the database storage area and writing the updated block back to the database storage area by the data access control unit, batch processing can overwrite the updated information on the block contents in the database storage area and refer to the contents at any time. Online processing allows the latest block contents to be referenced simply by accessing the database storage area.

[0007]

[Operation] In the version control processing method of the present invention, when the version control unit updates a block requested by a user program, before actually updating the block, it reads out the contents of the updated part before the update, and displays the update time and Since the set of update times given by the management section is registered as update information in the update item registration section, the contents before the update can be restored by overwriting the registered update information on the block contents after the update.

[0008] Therefore, the contents of a block at an arbitrary time specified by batch processing of a user program are added to the contents of the block read from the database storage area, including updates later than the specified time among update information related to the block. It can be generated by overwriting those that include the time in order from the one with the latest update time.

[0009] Furthermore, since block updates are performed directly in the database storage area at the time of request, when a block is referenced in online processing by a user program, the latest update of the block can be updated simply by accessing the database storage area. You can get the contents of

0010

[Embodiment] FIG. 1 is a diagram for explaining one embodiment of the present invention, in which 101 is a user program, 102 is a version management section, 103 is an update item registration area, 104 is an update time management section, and 105 is a diagram for explaining an embodiment of the present invention. A data access control unit 106 is a database storage area.

[0011] The database storage area 106 is a part that stores database records in blocks.
Each block has a one-to-one correspondence with a block identifier. The data access control unit 105 includes the version management unit 1
The function reads the block from the database storage area 106 based on the block identifier given from 02 and transfers it to the version management unit 102, and the block content is transferred to the database storage area 106 based on the block identifier and block content given from the version management unit 102. It also has a writing function.

The update time management unit 104 is a part that manages the current time, and provides time information to the version management unit 102. Note that the time information does not need to be the actual time itself, and may be logical information such as a sequence number of a request from the user program 101, for example. The user program 101 is a program that performs online processing or batch processing of a database by the user, and when referring to a block of the database through online processing, the block identifier of the block is
When updating a block using online processing, the block identifier of the block, information specifying the updated part within the block, and the content to be written to the updated part are used. When referring to the contents of a block at a specific time using batch processing, the information is the time and the information to be written to the updated part. The block identifier of the block is given to the version control unit 102.

When the version management unit 102 is requested to update a block through online processing by the user program 101, the version management unit 102 requests the data access control unit 105 for a block corresponding to the block identifier given by the user program 101. Read from the database storage area 106. Next, the content before the update of the updated part is extracted from the block read based on the updated part specification information given by the user program 101, and the retrieved content before the update and the updated content are requested to the update time management unit 104 and obtained. Update item registration area 10 with current time information as a set of update information
Register for 3. Finally, the content written to the updated part given by the user program 101 is written to the read block, and the data access control unit 105 is requested to send the written block to the database storage area 10.
Write back to 6.

FIG. 2 shows the update item registration area 10 in FIG.
3 is a diagram illustrating an example of the internal configuration of No. 3, in which 201 is an update information entry and 202 is a mapping section. The update information entry 201 includes one piece of the update information, and includes a pointer 203 indicating a chain between entries, a block identifier 204,
It consists of an update time 205, a relative start position 206 of the updated portion within the block, a length 207 of the updated portion, and a content 208 of the updated portion before the update. Update information entry 20
1 is grouped by update information related to blocks having the same hash value of block identifiers, and forms an entry list linked by a pointer 203 for each group.

The mapping unit 202 is the version management unit 1
This is a mechanism for quickly referencing or updating the update information entry 201 by the update information entry 201.
1 are grouped as in the above example, the corresponding entry list is obtained from the hash value of the block identifier given by the version control unit 102, and a pointer to the first entry of the list is returned to the version control unit 102. . The version management unit 102 uses the update information entry 20 to register the pointer returned from the mapping unit 202.
1 pointer 203.

When the version management unit 102 is requested to refer to a block through online processing by the user program 101, the version management unit 102 requests the data access control unit 105 for the block corresponding to the block identifier given by the user program 101. The blocks are read from the database storage area 106 and transferred to the user program 101 as they are.

When the version management unit 102 is requested to refer to a block at a specific time by batch processing of the user program 101, the version management unit 102 requests the data access control unit 105 for the block corresponding to the block identifier given by the user program 101. database storage area 106
Read from. Next, a request is made to the mapping unit 202 in the update item registration area 103 to obtain the entry list including update information related to the block. Finally, the obtained entry list is searched and the block identifier 204 of the update information entry 201 is equal to the one given by the user program 101, and the update time 205 is later than the time given by the user program 101. The information entry 201 is obtained, and the pre-update content 208 included in the obtained entry is set to the update part start position 206 and the update part length 2.
07, the read blocks are overwritten in order from the newest update time 205 to the oldest one, and the blocks that have been overwritten are returned to the user program 101.

[0018]

As explained above, according to the present invention, the database is updated by the user program directly in the database storage area, so that the secondary storage required when referencing one block in online processing is reduced. The device is accessed only once, and the real-time performance of online processing is not degraded by accessing the secondary storage device multiple times.

[0019] Also, since the content before update of the block to be updated is saved in the update item registration area along with the update time, the content before update is overwritten on the latest block content in the database storage area in the order of the latest update time. Then, the contents of the block at any time can be restored, and batch processing can always be performed on a database at any time without degrading the online processing service. The update item registration area can be provided in the memory of the main unit because the update information to be registered is the old content before the block was updated, so even if it is lost, the latest content of the database can be guaranteed. Therefore, even if it is necessary to access the contents at an older time, the contents of the block can be restored relatively quickly.

[Brief explanation of drawings]

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

FIG. 2 is a diagram showing the internal configuration of an update item registration area.

[Explanation of symbols]

101 User program 102 Version control department 103 Update item registration area 104 Update time management department 105 Data access control unit 106 Database storage area 201 Update information entry 202 Mapping section 203 Pointer 204 Block identifier 205 Update time 206 Update part start position 207 Update part length 208 Contents before update

Claims (1)

[Claims] Claim 1: In a database processing system in which online processing and batch processing are executed on the same database in a mixed manner, there is a database storage area that stores database records in blocks, and a block storage area for the database storage area. A data access control unit for reading or writing, an update time management unit for managing the block update time by the user program, and an update item registration area for registering block update information by the user program together with the update time. and a version management unit that registers update information in the update item registration area and overwrites the update information on block contents received from the data access control unit,
When the version control unit is requested to update a block by a user program that performs online processing, the version control unit requests the data access control unit to read the block from the database storage area, and updates the updated portion of the block before updating. and the update time given by the update time management unit as a set of update information in the update item registration area, and request the data access control unit to send the block that has undergone the requested update to the database. When a user program that writes to a storage area and performs batch processing requests to refer to the contents of a block at a specific time, the data access control unit is requested to read the block from the database storage area, and after the specific time. By overwriting the update information related to the block registered in the update item registration area over the read block contents in order from the latest update time, and having the user program refer to the block contents obtained by overwriting,
A version control processing method characterized by being able to form content at any time from the latest block content in a database storage area.