JPH07306802A - Data base management system - Google Patents

Abstract

PURPOSE:To shorten a backup time, to effectively utilize a secondary storage medium and a data base area, and to shorten the recovery time at data saving time. CONSTITUTION:An access frequency is decided according to the frequency of use of data, and a data necessary/unnecessary flag and a backup necessary/ unnecessary flag in a data management record 2a are set. A backup means 3 outputs data in a data base to the secondary storage medium 6 when the backup necessary/unnecessary flag indicates necessity and does not outputs the data when not. Further, data for which the data necessary/unnecessary flag indicates nonnecessity are outputted to the secondary storage medium 6 and the data are deleted from the data base 2. A recovery means 5 recovers the data whose data necessary/unnecessary flag indicates nonnecessity from the secondary storage medium 6 to the data base 2 by referring to the secondary storage medium information in the data management record 2a when a data access means 7 makes a request to access the said data. Further, even when the data base 2 is destroyed or erased owing to trouble, the data base 2 is recovered with the data on the secondary storage medium 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to how to manage and maintain data which increases daily in an information processing system using a database. In managing a large amount of data that is increasing day by day using a database that uses a computer storage device as a medium, the backup time for data preservation continues to increase. In addition, since the storage area of the database is decreasing, it is necessary to save data that is rarely used in the database, secure a storage area of the database, and manage the saved data. It is necessary to manage and maintain the data from the database quickly and efficiently while keeping all the data in the database safe in daily operation.

The present invention reduces the backup time, effectively uses the secondary storage medium, effectively uses the database area,
The present invention relates to reduction of recovery time when data is saved and simplification of save operation.

[0003]

2. Description of the Related Art In a conventional database management method, when a backup is acquired in preparation for a database failure, all data on the database is output to a secondary storage medium. Further, in the case where data that is used less frequently among the ever-increasing amount of data is output to the secondary storage medium to secure a data storage area, the data is manually specified and deleted, or an output program to the secondary storage medium is performed. Had to start and recover the data.

As a conventional technique relating to this type of database management system, for example, Japanese Patent Laid-Open No. 4-252342.
Techniques described in Japanese Patent Laid-Open No. 5-100935 and Japanese Patent Laid-Open No. 5-100935 are known.

[0005]

In the conventional database management method, all the data existing in the database are backed up regardless of the frequency of use.

For this reason, unused data is repeatedly stored in the secondary storage medium, and the backup time and the secondary storage medium are wasted. After deleting the data for the purpose of effective use of the area on the database, when the user needs it, the secondary storage medium name must be searched from the result information of the backup process, so it cannot be accessed immediately. There was a problem. Further, when a means for managing the secondary storage medium information of the data saved and saved from the database is provided on the database, it is necessary to perform the save and delete processes separately, which causes a work to operate the database.

The present invention solves the above-mentioned problems and provides a data necessary / unnecessary flag for each data in the database, and controls whether or not the data exists in the database. Further, a backup required / unnecessary flag is provided to control whether or not to perform backup. This aims to shorten the backup time, effectively use the secondary storage medium, effectively use the database area, shorten the recovery time when saving data, and simplify the save operation.

[0008]

FIG. 1 is a block diagram showing the structure of the present invention.

The flag setting means 1 sets / cancels the data necessary / unnecessary flag and the backup necessary / unnecessary flag in the data management record 2a according to the frequency of use of the data.

Further, the data management record 2a is deleted. When outputting the data in the database 2 to the secondary storage medium 6, the backup means 3 outputs the data to the secondary storage medium 6 when the backup required / unnecessary flag is required, and when the backup required / unnecessary flag is not required, the secondary No output to the storage medium 6. In addition, data that does not require the data required / unnecessary flag is 2
The data is output to the next storage medium 6 and the deleting means 4 is activated. The deleting unit 4 deletes the data targeted for the saving process from the database 2 based on the completion of the data saving process. The recovery unit 5 recovers data whose unnecessary / unnecessary data flag is unnecessary to the database from the secondary storage medium 6 when an access request is made by the data access unit 7, and destroys or damages the database 2 due to a hardware failure or a software failure. When erased, the database 2 is restored from the secondary storage medium 6. Further, the data management record 2a stores a data name, a processing target date (creation, update, input), a data necessary / unnecessary flag, a backup necessary / unnecessary flag, secondary storage medium information, and the like. The secondary storage medium refilling means 8 extracts only the data stored in the data management record 2a from the secondary storage medium 6,
Output to another secondary storage medium 6.

[0011]

According to the database management method of the present invention, data is classified into frequent access / intermediate access / frequent access / no access depending on the frequency of use of the data. Unnecessary flag required, data required / unnecessary flag required if access is in progress, backup required / unnecessary flag not required, data required / unnecessary flag not required, backup required / unnecessary flag not required, access not required If
The deleting means is activated to delete the data from the database, and the data management record is deleted. Therefore, for data having an intermediate use frequency, the flag setting means 1 eliminates the need / non-necessity flag for backup in the data management record 2a, and the backup means 3 suppresses output to the secondary storage medium. In addition, for data that is rarely used, the data management record 2 is set by the flag setting means 1.
Since the data required / unnecessary flag becomes unnecessary in a, the backup means 3 registers the information such as the volume name of the secondary storage medium in the data management record 2a together with the output to the secondary storage medium. After that, the deleting unit 4 deletes the data from the database 2. The data management record 2a when data access is requested from the data access means 7
If the data exists but the data does not exist in the database 2, the recovery unit 5 recovers the data from the information such as the volume name of the secondary storage medium recorded in the data management record 2a. When the database 2 is destroyed or erased due to a hardware error or a software error, the database 2 is recovered from the secondary storage medium 6.

[0012]

The present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of the database management system of the present invention. As shown in FIG. 1, the database management method includes a flag setting means 1, a database 2 having a data management record 2a, a backup means 3,
The deletion unit 4, the recovery unit 5, the secondary storage medium 6, the data access unit 7, and the secondary storage medium refilling unit 8 are included.

FIG. 2 shows the structure of the data management record 2a. In the data management record 2a, a data name, a processing target date (creation, update, input), a data necessary / unnecessary flag, a backup necessary / unnecessary flag, secondary storage medium information and the like are stored.

FIG. 3 is a flow chart showing an example of flag setting in the flag setting means 1. The flag setting means 1 is regularly or by a database operator.
It is started at any time. In step 1-1, the access frequency of the data is determined according to the usage period or the character of the data with reference to the data management record 2a for each data. For example, if the last access date is within 1 year from the current time, frequent access is performed if within 1 to 2 years, access is intermediate if within 2 years to 3 years, access is low, and if there is no access for 3 years or more, no access is determined. To do. If access is frequent, proceed to step 1-5. If it is in the middle of access, proceed to step 1-2. If there is little access, proceed to step 1-3. If there is no access, go to step 1-4. In step 1-2, data required for the data management record 2a /
The unnecessary flag is required, and the backup necessary / unnecessary flag is not required. In step 1-3, the data necessary / unnecessary flag of the data management record 2a is unnecessary, the backup necessary / unnecessary flag is unnecessary, and the step 1-5
Proceed to. In step 1-4, after activating the deleting means 4 to delete the corresponding data, the information of the corresponding data in the data management record 2a is deleted. In step 1-5, it is determined whether or not all the data in the database 2 have been processed. If it is not the end, return to step 1-1.

FIG. 4 is a flow chart showing an example of backup in the backup means 3. It is activated by the database operator regularly or at any time. Backup required for each data in step 3-1 /
It is determined whether the unnecessary flag is necessary. If the backup necessary / unnecessary flag is necessary, go to step 3-2. If the backup necessary / unnecessary flag is unnecessary, the process proceeds to step 3-4. In step 3-2, the data is output to the secondary storage medium 6, and the process proceeds to step 3-3. In step 3-3, information such as the volume name of the secondary storage medium is written in the data management record 2a, and the process proceeds to step 3-10. In step 3-4, it is determined whether the data required / unnecessary flag is required. If the data required / unnecessary flag is required, the process proceeds to step 3-11. If the data required / not required flag is unnecessary,
Go to step 3-5. In step 3-5, it is determined whether or not there is a data presence / absence flag. If the data presence / absence flag is present, the process proceeds to step 3-6. If the data presence / absence flag is not present, the process proceeds to step 3-10. Step 3
In -6, the data is output to the secondary storage medium 6, and the process proceeds to step 3-7. In step 3-7, the information of the secondary storage medium that has output the data is set to the data management record 2a.
And register to step 3-8. In step 3-8, the saved data is deleted by activating the deleting means 4 in FIG. 5, and then the process proceeds to step 3-9. In step 3-9, the data existence / non-existence flag in the data management record 2a is set to "no", and the process proceeds to step 3-10. In step 3-10, it is determined whether all the data in the database 2 have been processed, and if the processing is completed, the processing is terminated. If it is not the end, return to step 3-1. Step 3-1
In 1, the presence or absence of secondary storage medium information in the data management record is checked, and if there is no secondary storage medium information, step 3-
Go to 2. If there is secondary storage medium information, step 3-1.
Go to 0.

FIG. 5 is a flow chart showing an example of deletion by the deleting means 4. The deleting means 4 is activated by the backup means 3. In step 4-1, the data is deleted, and the process ends.

FIG. 6 is a flow chart showing an example of recovery by the recovery means 5. In step 5-1, the storage volume name of the data is known from the data management record 2a, the data is stored in the database 2 from the secondary storage medium 6, and the process proceeds to step 5-2. In step 5-2, the data required / unnecessary flag of the data in the data management record 2a is required, the backup required / unnecessary flag is required, and the data presence / absence flag is set, and the process is ended.

FIG. 7 is a flow chart showing an example of data access by the data access means 7. In step 7-1, it is determined whether or not the data is read. If data is read, the process proceeds to step 7-2. If the data is not read, the process proceeds to step 7-7. In step 7-2,
It is determined whether or not there is data in the data management record 2a. If there is no data in the data management record 2a, the process proceeds to step 7-3. If there is data in the data management record 2a, the process proceeds to step 7-4. Step 7
At -3, an error message is output and the process ends.
In step 7-4, it is determined whether the data required / unnecessary flag is required. If the data necessary / unnecessary flag is unnecessary, the process proceeds to step 7-5. If the data required / unnecessary flag is required, the process proceeds to step 7-6. In step 7-5, the recovery means 5 in FIG. 6 is activated to perform recovery processing, and then the process proceeds to step 7-6. At step 7-6, access is performed and the process is terminated. At step 7-7, it is judged whether or not the data is written. If data writing, proceed to step 7-8. If the data is not written, the process proceeds to step 7-10. In step 7-8, data is written, and the process proceeds to step 7-9. In step 7-9, the information regarding the data is added to the data management record 2a, the data required / unnecessary flag is required, the backup required / unnecessary flag is required, and the data presence / absence flag is present, and the process is terminated.
In step 7-10, it is determined whether or not the data is deleted. If the data is deleted, the process proceeds to step 7-11. If the data is not deleted, the process proceeds to step 7-12. Step 7-
In 11, the deleting unit 4 is activated to perform the deleting process, and then the process ends. In step 7-12, an error message is output and the process ends.

FIG. 8 is a flow chart showing an example of refilling the secondary storage medium in the refilling means 8 for the secondary storage medium. In step 8-1, the data is copied to the refilled secondary storage medium based on the secondary storage medium information in the data management record 2a, and the process proceeds to step 8-2. Step 8
-2, the secondary storage medium information in the data management record 2a is updated, and then the process proceeds to step 8-3. In step 8-3, it is determined whether or not all the data in the database 2 have been processed. If the processing is completed, the processing is ended. If it is not the end, return to step 8-1.

[0021]

As described above, according to the database management method of the present invention, the frequency of use of data is determined, and the backup processing is not performed for data with low frequency of use, so that the backup time can be shortened. Further, since it is possible to prevent the unused data from being repeatedly stored in the backup secondary storage medium, the number of secondary storage media can be reduced. For data that is used infrequently, the area can be effectively used because it is saved in the secondary storage medium in the backup process and deleted from the database. Moreover, since the secondary storage medium information storing the saved data is stored in the database, the search time can be reduced,
Data recovery time can be shortened. Since data is backed up and deleted by the backup process that is performed in normal operation, database operation can be simplified without any special operation.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a database management system of the present invention.

FIG. 2 is a diagram showing an example of a data management record.

FIG. 3 is a flowchart showing an example of flag setting in a flag setting means.

FIG. 4 is a flowchart showing an example of backup in the backup means.

FIG. 5 is a flowchart showing an example of deletion by a deleting means.

FIG. 6 is a flowchart showing an example of recovery by a recovery means.

FIG. 7 is a flowchart showing an example of data access by a data access unit.

FIG. 8 is a flowchart showing an example of secondary storage medium refilling in the secondary storage medium refilling means.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Flag setting means, 2 ... Database, 2a ... Data management record, 3 ... Backup means, 4 ... Deletion means, 5 ... Recovery means, 6 ... Secondary storage medium, 7 ... Data access means, 8 ... Secondary storage medium Is a means of refilling.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masayoshi Minoda 1 Horiyamashita, Hadano City, Kanagawa Prefecture Hitachi Computer Engineering Co., Ltd. (72) Inventor Kao Yamauchi 1 Horiyamashita, Hadano City, Kanagawa Prefecture Hitachi Computer Data Engineering Co., Ltd. (72) Inventor Yu Osawa 1 Horiyamashita, Hadano City, Kanagawa Prefecture

Claims (2)

[Claims] 1. In a database system, a data necessary / unnecessary flag, that is, a flag indicating whether or not data is to exist in the database, and a backhoop necessary / unnecessary flag, that is, a flag indicating whether a backup process is necessary. And a data management record that stores secondary storage medium information, etc., and depending on how often the data is used, frequent access (data exists in the database because data is frequently accessed and backups are acquired) / intermediate access (In order to shorten the access time at the time of data access request, the data exists in the database, but backup is not acquired) / Access is very small (data does not exist in the database and backup is not acquired, but at the time of access request, Recover from secondary storage medium) / no access Data is classified into (delete data and data management records from the database). If access is frequent, data required / unnecessary flag is required, backup required / unnecessary flag is required, if access is in progress data required / unnecessary flag Required, backup required / unnecessary flag not required, data required / unnecessary flag not required if access is infrequent, backup required / unnecessary flag not required, and deletion means activated to delete data from the database if no access And a flag setting means having a function of deleting the data management record corresponding to the data, and outputting the data in the database to the secondary storage medium,
If the backup required / unnecessary flag is required, the data is output to the secondary storage medium. If the backup required / unnecessary flag is not required, the data is not output to the secondary storage medium. Is output to the secondary storage medium,
A backup means for activating the deleting means, a deleting means for deleting the data that is the object of the saving process from the database, and a secondary storage medium when the data access means requests access to data for which the data required / unnecessary flag is unnecessary. Recovers to a database, requires a data required / unnecessary flag, requires a backup required / unnecessary flag, and is a secondary storage medium when the database is destroyed or erased due to a hardware failure or software failure. A recovery means for further recovering the database, and a secondary storage medium refilling means for extracting only the data registered in the data management record from the secondary storage medium and creating another secondary storage medium are provided. Database management method. 2. The flag setting means according to claim 1, wherein the read-only data is classified as frequent access / intermediate access / frequent access / no access according to the nature of the data such that backup is unnecessary. If so, the data required / unnecessary flag is required, the backup required / unnecessary flag is required, if the access is in progress, the data required / unnecessary flag is required, the backup required / unnecessary flag is unnecessary, and if the access is few, the data required / unnecessary flag is required. Is a database management method that has a function of activating a deleting means to delete data from the database and deleting a data management record if there is no need, a backup necessary / unnecessary flag is unnecessary, and there is no access.