JP4494085B2 - Data management device - Google Patents

Description

  The present invention relates to a data management apparatus configured by a database or the like and performing data backup and restoration.

The differential backup of data in a database is a method for speeding up backup by setting only data that has been added, updated, or deleted since the last full backup as a backup target.
A differential backup in a conventional data management apparatus is a method for managing history information of addition, update, and deletion with respect to data registered in a database, and making only the changed data a database backup target (for example, patents) This is the first backup after transitioning to a non-updatable attribute and a file with an updatable attribute at the time of differential backup. Speedup has been performed using a method of limiting the backup target by setting the file as a backup target (see, for example, Patent Document 2).

JP 2002-13561 A JP 2003-316634 A

Since the conventional data management apparatus is configured as described above, the method disclosed in Patent Document 1 has to update history information when registering, updating, and deleting data, and the processing becomes complicated. There is a problem that it takes time to process. In addition, when recovery is performed when a failure occurs in the database, there is a problem that recovery must be performed in units of data based on history information, and recovery takes time.
In addition, the technique disclosed in Patent Document 2 has a problem that data that has not been updated or deleted to manage a plurality of data in units of files is also subject to differential backup. In addition, when registering, updating, and deleting data, it is necessary to change the attribute of the file and manage the transition state, which complicates the processing and takes time.

  The present invention has been made to solve the above-described problems, and provides a data management device that specifies data to be backed up with the minimum necessary information, and that simplifies and speeds up backup processing. The purpose is to obtain.

The data management apparatus according to the present invention includes information storage means for storing entity management information for managing the end of the reference area of the data storage means and backup start data information for specifying the head of the backup target in the reference area of the data storage means, Based on the entity management information, the data stored in the update area of the data storage means is added to the reference area, the data added to the reference area is deleted from the update area, and the entity is changed according to the data change in the data storage means. Data management means for updating management information, data specified based on backup start data information and entity management information is acquired from a reference area stored in the data storage means, and the specified data and update area of the reference area Operation processing that performs backup processing for all data and entity management information stored in the information storage means It is obtained by a means.

According to the present invention, only by referring to the backup start data information and entity management information, it is possible to identify the data to be backed up, there is an effect that it is possible to perform the backup at a high speed.

Embodiment 1 FIG.
FIG. 1 is a block diagram showing a data management apparatus 1 according to Embodiment 1 of the present invention. In the figure, the data management apparatus 1 is constituted by a database or the like. The application program 2 is a higher-level program that uses the data management apparatus 1. The data management unit (data management means) 3 receives a request from the application program 2 and performs data registration processing, update processing, and deletion processing. The operation processing unit (operation processing means) 4 receives a request from the application program 2 and performs backup of data held by the data management apparatus 1, restoration to restore backup data, and connection of backup files. The data access unit 5 accesses the data storage area (data storage means) 6, the entity management table 7, and the backup start record information 8 which are information held by the data management apparatus 1. The data storage area 6 manages the substance of registered data. The entity management table 7 manages whether or not the registered data is logically present. The backup start record information 8 manages information for specifying a record to be backed up at the time of backup. The backup medium 9 is a medium for saving a backup file. The entity management table 7 and the backup start record information 8 are stored in an information storage device (not shown), but this information storage device may be included in the data storage area 6.

Next, the operation will be described.
First, a data management method of the data management apparatus 1 will be described. FIG. 2 is an explanatory diagram showing a data storage format in the data storage area 6. The data storage area 6 includes a reference area 61, an update area 62, and record access information 63. Each of the reference area 61 and the update area 62 may be a single file, or may be secured as a physically continuous area. One record in the reference area 61 and the update area 62 corresponds to one data registered by the application program 2. Each record has a unique record number in the reference area 61 and the update area 62. 2, record 1 is a record with a record number 1, record 2 is a record with a record number 2,..., Record N is a record with a record number N. In the reference area 61 and the update area 62, records are continuously arranged from the top of each area. The record may be a fixed-length record having the same size for each record, or a variable-length record having a different size for each record. The update area 62 is an area where a record is added during registration processing and update processing of the application program 2. The data management apparatus 1 performs an optimization process for periodically adding records in the update area 62 to the reference area 61. The reference area 61 is an area where the state of the record does not change except that the record of the update area 62 is added by the optimization process. The record access information 63 is information for accessing the records stored in the reference area 61 and the update area 62, and includes a record number 65, an offset 66, and a size 67. When the reference area 61 and the update area 62 are each configured as one file, the offset may be an offset starting from the beginning of each file. When the reference area 61 and the update area 62 are secured as physically continuous areas, the offset may be an offset starting from the beginning of each physical area. When the record is a fixed-length record and the offset to each record is obtained by calculation, the record access information 63 is not essential.

  FIG. 3 is an explanatory diagram showing a data storage format of the entity management table 7. The entity management table 7 includes a total record number 71 that is information on the total number of records in the data storage area 6, a reference area record number 72 that is information on the total number of records in the reference area 61, and a record number 73 corresponding to each record. , Information on logical ID 74 and deletion flag 75 is managed. The logical ID 74 is information provided by the application program 2 and can uniquely identify a record stored in the reference area 61 or the update area 62 based on the logical ID 74. The deletion flag 75 is information indicating whether or not the record is logically deleted in the data storage area 6. When a record is logically deleted in the data storage area 6, 1 is assigned to the deletion flag 75 of the corresponding record. A record having a deletion flag 75 of 1 is treated as a deleted record for the application program 2. The entity management table 7 performs management so that a logical contradiction between records does not occur. That is, there may be a plurality of records having the same logical ID 74 in the entity management table 7, but there are only zero or one record with the deletion flag 75 being 0 among them.

  Next, data registration processing of the data management apparatus 1 will be described. FIG. 4 is a flowchart showing the data registration process of the data management apparatus 1. First, in step ST11, the data management unit 3 accepts a registration request for the application program 2. The application program 2 makes a registration request to the data management unit 3 by specifying data to be registered and a logical ID. Next, in step ST12, the data management unit 3 converts the data received in step ST11 into a record format managed by the data storage area 6. Next, in step ST13, the data management unit 3 makes a record addition request to the data access unit 5 by designating the record created in step ST12 and the logical ID received in step ST11. Next, in step ST14, the data access unit 5 performs a duplication check of the logical ID specified in step ST13. The duplication check refers to the entity management table 7, and an error occurs when there is a record having the same logical ID 74 as the logical ID specified in step ST13 and the deletion flag 75 being 0. If an error occurs in the duplication check, the process proceeds to step ST14: YES, and in step ST15, the data access unit 5 informs the data management unit 3 that a record having the logical ID specified in step ST13 has already been registered. Tell. If no error has occurred in the duplication check, the process proceeds to step ST14: NO. In step ST16, the data access unit 5 refers to the value N of the total number of records 71 in the entity management table 7, and records N in the update area 62 After that, the record designated in step ST13 is added. At this time, when the data storage area 6 has the record access information 63, information of the offset 66 and the size 67 of the record N + 1 is added. Next, in step ST17, the data access unit 5 adds the information of the record N + 1 to the entity management table 7. At this time, the logical ID 74 is set to the logical ID specified in step ST13, and the deletion flag 75 is set to 0. Also, the value of the total number of records 71 in the entity management table 7 is updated to N + 1.

  Next, the data deletion process of the data management apparatus 1 will be described. FIG. 5 is a flowchart showing data deletion processing of the data management apparatus 1. First, in step ST21, the data management unit 3 accepts a deletion request for the application program 2. At this time, the application program 2 designates a logical ID of data to be deleted. Next, in step ST22, the data management unit 3 makes a record deletion request to the data access unit 5 by designating the logical ID received in step ST21. Next, in step ST23, the data access unit 5 checks the presence of the logical ID specified in step ST22. In the presence check, the entity management table 7 is referred to, and an error is generated when there is no record having the same logical ID 74 as the logical ID specified in step ST22 and the deletion flag 75 being 0. If an error occurs in the existence check, the process proceeds to step ST23: NO, and in step ST24, the data access unit 5 informs the data management unit 3 that there is no record having the logical ID specified in step ST22. If no error has occurred in the existence check, the process proceeds to step ST23: YES, and in step ST25, the data access unit 5 changes the value of the deletion flag 75 of the record found in step ST23 to 1.

  Next, data update processing of the data management apparatus 1 will be described. FIG. 6 is a flowchart showing data update processing of the data management apparatus 1. First, in step ST31, the data management unit 3 receives an update request for the application program 2. The application program 2 makes an update request to the data management unit 3 by designating the logical ID of the data to be updated and the update data. Next, in step ST32, the data management unit 3 converts the update data received in step ST31 into a record format managed by the data storage area 6. Next, in step ST33, the data management unit 3 makes a record update request to the data access unit 5 by designating the record created in step ST32 and the logical ID received in step ST31. Next, in step ST34, the data access unit 5 checks the existence of the logical ID specified in step ST33. In the existence check, the entity management table 7 is referred to, and an error is generated if there is no record having the same logical ID 74 as the logical ID specified in step ST33 and the deletion flag 75 is 0. If an error occurs in the existence check, the process proceeds to step ST34: NO, and in step ST35, the data access unit 5 notifies the data management unit 3 that there is no record having the logical ID specified in step ST33. If no error has occurred in the existence check, the process proceeds to step ST34: YES, and the data access unit 5 changes the value of the deletion flag 75 of the record found in step ST34 to 1. Next, in step ST37, the data access unit 5 refers to the value N of the total number of records 71 in the entity management table 7. The data access unit 5 adds the record specified in step ST33 after the record N in the update area 62. When the data storage area 6 has the record access information 63, information on the offset 66 and the size 67 of the record N + 1 is added. Next, in step ST38, the data access unit 5 adds the information of the record N + 1 to the entity management table 7. At this time, the logical ID 74 is set to the logical ID specified in step ST33, and the deletion flag 75 is set to 0. Further, the information on the total number of records 71 in the entity management table 7 is updated to N + 1.

  Next, the optimization process of the data management apparatus 1 will be described. FIG. 7 is a flowchart showing the optimization process of the data management apparatus 1. The optimization process is a process for adding the record in the update area 62 to the reference area 61 and is periodically executed by the data management unit 3. First, in step ST41, the data management unit 3 makes a record optimization request to the data access unit 5. Next, in step ST42, the data access unit 5 refers to the entity management table 7, and acquires the value M of the reference area record number 72 and the value N of the total record number 71 (M ≦ N). Further, in step ST43, the data access unit 5 determines whether or not all the records in the update area 62 have been added to the reference area 61. If it is determined that the values of M and N satisfy M <N, the process proceeds to step ST43: YES, and step ST44 is executed. If M <N is not satisfied, the process proceeds to step ST43: NO, and step ST46 is executed. In step ST <b> 44, the data access unit 5 adds the record M + 1 in the update area 62 after the record M in the reference area 61. When the data storage area 6 has the record access information 63, information on the offset 66 and the size 67 of the record M + 1 is added. In step ST45, the data access unit 5 increments the value of M by 1 and executes the process of step ST43. Further, in step ST46, the data access unit 5 deletes all the records in the update area 62. When managing each of the reference area 61 and the update area 62 as one file, the data access unit 5 may empty the file in the update area 62. When the reference area 61 and the update area 62 are secured as physically continuous areas, the data access unit 5 may initialize the update area 62. Finally, in step ST47, the data access unit 5 updates the value of the reference area record number 72 in the entity management table 7 to N.

  Next, backup processing of data held by the data management device 1 will be described. In the data management apparatus 1, the data to be backed up are the data storage area 6 and the entity management table 7. There are three types of backups: full backup, differential backup, and incremental backup. The full backup is a process for performing backup for all data held by the data management apparatus 1. The differential backup is a process for performing backup on data updated from the time of the last full backup. Incremental backup is a process for performing backup on data updated since the last full backup, differential backup, or incremental backup.

  Here, the backup process of the data management apparatus 1 will be described. FIG. 8 is an explanatory diagram showing the backup start record information 8. The backup start record information 8 is recorded with information for specifying a record to be backed up at the time of differential backup or incremental backup. FIG. 9 is a flowchart showing the backup processing of the data management apparatus 1. FIG. 10 is an explanatory diagram showing the structure of the backup file 10 created by the data management apparatus 1 during backup.

  First, in step ST51, the operation processing unit 4 receives a backup request for the application program 2, generates the backup file 10, and writes the creation date 101. At this time, the application program 2 designates full backup, differential backup, or incremental backup as the backup type. Next, in step ST52, the operation processing unit 4 refers to the entity management table 7, and acquires the value N of the total record number 71 and the value M of the reference area record number 72. Next, in step ST53, the operation processing unit 4 backs up the reference area 61.

  Here, the backup process of the reference area 61 will be described in detail. First, in step ST64, the operation processing unit 4 obtains a set of records to be backed up in the reference area 61. In the set of records, the record number of the first record is S1, and the record number of the last record is T1. Here, if the backup type specified in step ST51 is a full backup, the value of S1 is set to 1. In the case of differential backup, the backup start record information 8 is referred to, and the value of the record number 82 of the differential backup with the backup type 81 is set as the value of S1. In the case of incremental backup, the backup start record information 8 is referred to, and the value of the record number 82 of the incremental backup of the backup type 81 is set as the value of S1. The value of T1 is a value M of 72 reference area records in the entity management table 7. Next, in step ST65, the operation processing unit 4 obtains the storage start position U1 and the storage size V1 as information for specifying the storage position in the reference area 61 from the record S1 to the record T1. At this time, when the data storage area 6 has the record access information 63, the storage start position U1 can be obtained by “offset of record S1”, and the storage size V1 can be obtained by “offset of record T1 + size of record T1”. When the data storage area 6 does not have the record access information 63 and is a fixed-length record with a record length of L, the storage start position U1 is “(S1-1) × L”, and the storage size V1 is “(T1-S1 + 1). ) × L ”. Next, in step ST66, the operation processing unit 4 acquires data of the reference area 61 via the data access unit 5 based on the storage start position U1 and the storage size V1 obtained in step ST65. Next, in step ST67, the operation processing unit 4 writes the record number of the record S1 to the reference area start record number 102 of the backup file 10, and writes the record number of the record T1 to the reference area end record number 103 of the backup file. Further, the data of the reference area 61 acquired in step ST66 is written into the reference area data 112 of the backup file 10. Further, the reference area data offset 104 is written as information for accessing the reference area data 112 in the backup file 10, and the storage size V1 obtained in step ST65 is written in the reference area data size 105.

  Next, the operation processing unit 4 performs a backup process for the update area 62. Since all the records in the update area 62 are to be backed up, the operation processing unit 4 acquires the data of all the records stored in the update area 62 via the data access unit 5 in step ST54. In step ST55, the operation processing unit 4 writes the record data of the update area 62 acquired in step ST54 into the update area data 113 of the backup file 10. In addition, the update area data offset 106 and the update area data size 107 are written as information for accessing the update area data 113 in the backup file 10.

  Next, the operation processing unit 4 performs a backup process of the record access information 63. In step ST56, if the data storage area 6 has the record access information 63, the process proceeds to step ST56: YES, and if not, the process proceeds to step ST56: NO. In step ST57, the operation processing unit 4 acquires the data of the record access information 63 via the data access unit 5, and writes it in the record access information data 114 of the backup file 10 in step ST58. At this time, the record access information data offset 108 and the record access information data size 109 are written as information for accessing the record access information data 114 in the backup file 10.

  Next, the operation processing unit 4 performs backup processing of the entity management table 7. First, in step ST59, the operation processing unit 4 acquires the data of the entity management table 7 via the data access unit 5. Next, in step ST60, the operation processing unit 4 writes the data of the entity management table 7 acquired in step ST59 into the entity management table data 115 of the backup file 10. At this time, the entity management table data offset 110 and the entity management table data size 111 are written as information for accessing the entity management table data 115 in the backup file 10.

  Finally, the operation processing unit 4 updates the backup start record information 8. In step ST61, the operation processing unit 4 updates the value of the record number 82 whose backup type 81 is incremental backup to M + 1 via the data access unit 5. Also, only when the backup type specified in step ST51 is a full backup, the value of the record number 82 in which the backup type 81 is a differential backup is updated to M + 1.

  Next, data restoration processing of the data management apparatus 1 will be described. FIG. 11 is a flowchart showing a restore process of the data management apparatus 1, and FIG. 12 is an explanatory diagram showing a storage format of data in the backup file and data storage area 138, which will be described together with the backup file 10 of FIG. First, the operation processing unit 4 receives a restore request from the application program 2. At this time, the application program 2 designates N (1 ≦ N) backup files 10 necessary for restoring the data management apparatus 1. In FIG. 12, a backup file A120, a backup file B125, and a backup file C130 are designated and N = 3, and the data storage area 138 and the entity management table 145 are restored using these backup files. Next, in step ST72, the operation processing unit 4 checks whether the data management apparatus 1 can be restored using the N backup files 10 designated in step ST71. The operation processing unit 4 determines that restoration is possible when the record number held in the N backup files 10 is held without duplication or omission from the record with 1 record. In FIG. 12, the backup file A120 holds records 1 to k, the backup file B125 holds records k + 1 to L, and the backup file C130 holds records L + 1 to M, so that the information of records 1 to M is not duplicated or missing. Since it is retained, it is determined that restoration is possible. If it is determined in step ST72 that restoration is possible, the process proceeds to step ST72: YES, and the reference area 61 is restored in step ST74. If it is determined in step ST72 that restoration is not possible, the process proceeds to step ST72: NO, and error information is returned to the application program 2 in step ST73.

  Here, the restoration process of the reference area 61 will be described in detail. The reference area 61 is restored by the operation processing unit 4 writing all the reference area data 112 held by the N backup files 10 designated in step ST71 into the reference area 61. In FIG. 12, restoration is performed by writing the reference area data 124 held by the backup file A120, the reference area data 129 held by the backup file B125, and the reference area data 134 held by the backup file C into the reference area 139.

  First, in step ST82, the operation processing unit 4 sets the value of the write position WP to 0. The write position WP is information for specifying the position where the reference area data 112 is written in the reference area 61 and is an offset with the head of the reference area 61 as a base point. In FIG. 12, the value of the write position WP is set to 0 to indicate the beginning of the reference area 139. Next, in step ST83, the operation processing unit 4 selects the backup file 10 with the oldest creation date 101 among the unprocessed backup files 10. In FIG. 12, the backup file A120 is selected. Next, in step ST84, the operation processing unit 4 acquires the reference area data 112 based on the reference area data offset 104 and the reference area data size 105 of the backup file 10 selected in step ST83, and passes through the data access unit 5. Thus, writing is performed from the position of the writing position WP in the reference area 61. In FIG. 12, the reference area data 124 is written from the top of the reference area 139 and written in the reference area 140. Next, in step ST85, the operation processing unit 4 adds the value of the reference area data size 105 of the backup file 10 selected in step ST83 to the write position WP. In FIG. 12, the size of the reference area data 124 is added to the value of the write position WP. Next, in step ST86, it is determined whether or not the restoration of the reference area 61 has been completed. If all of the N backup files 10 have been processed, the process proceeds to step ST86: YES, and the restoration of the reference area 61 is completed. If there is an unprocessed backup file 10, the process proceeds to step S83. In FIG. 12, the processing from step ST83 to step ST85 is performed on the backup file B125 and the backup file C130. As a result, the reference area data 129 is written in the reference area 141 and the reference area data 134 is written in the reference area 142.

  Next, in step ST75, the operation processing unit 4 selects the backup file 10 with the latest creation date 101 from among the N backup files 10 designated in step ST71. In FIG. 12, the backup file C130 is selected. In step ST76, the operation processing unit 4 acquires the update region data 113 based on the update region data offset 106 and the update region data size 107 of the backup file 10 selected in step ST75, and updates the update region via the data access unit 5. Write from the beginning of 62. In FIG. 12, the update area data 135 is written into the update area 143. Next, in step ST77, the operation processing unit 4 acquires the entity management table data 115 based on the entity management table data offset 110 and the entity management table data size 111 of the backup file 10 selected in step ST75, and the data access unit 5 from the beginning of the entity management table 7. In FIG. 12, entity management table data 137 is written to the entity management table 145. Next, in step ST78, if the data storage area 6 has the record access information 63, the process proceeds to step ST78: YES, and the process of step ST79 is performed. Otherwise, the process proceeds to step ST78: NO. In step ST79, the operation processing unit 4 acquires the record access information data 114 based on the record access information data offset 108 and the record access information data size 109 of the backup file 10 selected in step ST75, and passes through the data access unit 5. Write from the top of the record access information 63. In FIG. 12, the record access information data 136 is written in the record access information 144.

  Next, processing when the data management apparatus 1 creates a single backup file 10 by connecting a plurality of backup files 10 will be described. FIG. 13 is a flowchart showing the backup file connection process of the data management apparatus 1, and FIG. 14 is an explanatory diagram showing the backup files 150, 156, 162, 180, which will be described together with the backup file 10 of FIG. First, in step ST91, the operation processing unit 4 receives a connection request from the application program 2, creates a backup file 10 after connection, and writes the creation date 101. At this time, the application program 2 designates N backup files 10 to be connected (1 <N). In FIG. 14, backup A 150, backup B 156, and backup C 162 are designated and N = 3, and a backup file D 180 after linking is created and the creation date 181 is written. Next, in step ST92, the operation processing unit 4 checks whether the N backup files 10 designated in step ST91 can be connected. The operation processing unit 4 determines that connection is possible when N backup files 10 hold records in the reference area 61 without duplication or omission. In FIG. 14, the backup file A 150 holds records J to K, the backup file B 156 holds records K + 1 to L, and the backup file C 162 holds information of records L + 1 to M, and holds information of the record J + M without duplication or omission. Therefore, it is determined that connection is possible. If it is determined in step ST92 that connection is possible, the process proceeds to step ST92: YES, and reference region data 112 is connected in step ST94. If it is determined in step ST92 that the connection is impossible, the process proceeds to step ST92: NO, and error information is returned to the application program 2 in step ST93.

  Here, the connection process of the reference area data 112 will be described in detail. The reference area data 112 is linked by the operation processing unit 4 writing all the reference area data 112 held by the N backup files 10 designated in step ST91 into the combined backup file 10. In FIG. 14, the reference area data 155, the reference area data 161, and the reference area data 170 are written in the backup file D180 to link the reference area data.

  First, in step ST102, the operation processing unit 4 sets the value of the write position FP to 0. The write position FP is information for specifying a position to write the reference area data 112 of the N backup files 10 used for concatenation in the backup file 10 after concatenation. The write position FP is the information of the reference area data 112 of the backup file 10 after concatenation. This is the offset starting from the beginning. In FIG. 14, the write position FP is an offset starting from the beginning of the reference area data 192, and setting the FP to 0 indicates the beginning of the reference area data 192. Next, in step ST103, the operation processing unit 4 selects the backup file 10 with the oldest creation date 101 among the unprocessed backup files 10. In FIG. 14, the backup file A150 is selected. Next, in step ST104, the operation processing unit 4 acquires the reference area data 112 based on the reference area data offset 104 and the reference area data size 105 of the backup file 10 selected in step ST103, and the backup file 10 after concatenation. Write from the position of the write position FP. In FIG. 14, the reference area data 155 is written from the beginning of the reference area data 192 and is written in the reference area data 193 portion. Next, in step ST105, the operation processing unit 4 adds the value of the reference area data size 105 of the backup file 10 selected in step ST103 to the write position FP. In FIG. 14, the reference area data size 154 is added to the value of the write position FP. Next, in step ST106, it is determined whether or not the connection of the reference area data 112 is completed. When all the N backup files 10 designated in step ST91 have been processed, the process proceeds to step ST106: YES, and the process of step ST107 is performed. If there is an unprocessed backup file 10, the process proceeds to step ST106: NO, and step ST103 is executed. In FIG. 14, the processing from step ST103 to step ST105 is performed on the backup file B156 and the backup file C162. As a result, the reference area data 161 is written in the reference area data 194 portion, and the reference area data 170 is written in the reference area data 195 portion. Next, in step ST107, the operation processing unit 4 adds the value of the reference area first record number 102 of the backup file 10 with the oldest creation date 101 among the N backup files 10 specified in step ST91 after concatenation. Is written in the reference area first record number 102 of the backup file 10. Further, the reference area end record number 103 of the backup file 10 with the latest creation date 101 among the N backup files 10 designated in step ST91 is used as the reference area end record number 103 of the backup file 10 after concatenation. Write to. Further, information for accessing the reference area data 112 in the backup file 10 after connection is written in the reference area data offset 104 of the backup file 10 after connection, and the reference areas of the N backup files 10 specified in step ST91. The sum of the data sizes 105 is written into the reference area data size 105 in the backup file 10 after concatenation. In FIG. 14, the value of the reference area first record number 152 is written in the reference area first record number 182 and the value of the reference area end record number 165 is written in the reference area end record number 183. In addition, information for accessing the reference area data in the backup file D180 is written in the reference area data offset 184, and the total of the reference area data size 154, the reference area data size 160, and the reference area data size 166 is referred to as the reference area data size 185. Write to.

  Next, the operation processing unit 4 performs a connection process for the update area data 113. In step ST95, the operation processing unit 4 selects the backup file 10 having the latest creation date 101 among the N backup files 10 designated in step ST91. In FIG. 14, the backup file C162 is selected. Next, in step ST96, the operation processing unit 4 acquires the update area data 113 based on the update area data offset 106 and the update area data size 107 of the backup file 10 selected in step ST95, and the backup file 10 after concatenation. Is written in the update area data 113. At this time, information for accessing the update area data 113 in the backup file 10 after connection is written to the update area data offset 106 of the backup file 10 after connection, and the update area data size of the backup file 10 selected in step ST95. 107 is written in the update area data size 107 of the backup file 10 after concatenation. In FIG. 14, the update area data 171 is written into the update area data 196. At this time, information for accessing the update area data 196 in the backup file D180 is written in the update area data offset 186, and the update area data size 167 is written in the update area data size 187.

  Next, the operation processing unit 4 performs connection processing of the entity management table data 115. In step ST97, the operation processing unit 4 acquires the entity management table data 115 based on the entity management table data offset 110 and the entity management table data size 111 of the backup file 10 selected in step ST95, and the concatenated backup file 10 Is written in the entity management table data 115. At this time, information for accessing the entity management table data 115 in the linked backup file 10 is written in the entity management table data offset 110 of the linked backup file 10. Further, the entity management table data size 111 of the backup file 10 selected in step ST95 is written into the entity management table data size 111 of the backup file 10 after connection. In FIG. 14, the entity management table data 173 is written into the entity management table data 198. At this time, information for accessing the entity management table data 198 in the backup file D180 is written in the entity management table data offset 190, and the entity management table data size 169 is written in the entity management table data size 191.

  Next, the operation processing unit 4 performs a concatenation process for the record access information data 114. In step ST98, if the backup file 10 selected in step ST95 has the record access information data 114, the process proceeds to step S98: YES, and step ST99 is executed. Otherwise, the process proceeds to step ST98: NO, and the connection process is terminated. In step ST99, the operation processing unit 4 acquires the record access information data 114 based on the record access information data offset 108 and the record access information data size 109 of the backup file 10 selected in step ST95, and the backup file 10 after concatenation. Is written in the record access information data 114. At this time, information for accessing the record access information data 114 in the backup file 10 after concatenation is written in the record access information data offset 108 of the backup file 10 after concatenation. Further, the record access information data size 109 of the backup file 10 selected in step ST95 is written into the record access information data size 109 of the backup file 10 after concatenation. In FIG. 14, the record access information data 172 is written into the record access information data 197. In addition, information for accessing the record access information data 197 in the backup file D180 is written in the record access information data offset 188, and the record access information data size 168 is written in the record access information data size 189.

As described above, according to the first embodiment, at the time of backup processing, the record to be subjected to differential backup and incremental backup can be specified only by referring to the first record number 82 that is the target of the backup start record information 8. Therefore, it is not necessary to refer to the update history information of each record at the time of backup, and backup processing can be performed easily and at high speed.
Further, the record number 82 of the backup start record information 8 only needs to be updated at the time of differential backup processing, and the record number 82 of the backup start record information 8 only needs to be updated at the time of backup. Therefore, it is not necessary to manage record registration, update, and deletion history information for backup, and backup can be performed easily and at high speed.
Furthermore, when data is restored, it is not restored in units of records, but is restored in units of reference area 61 and update area 62, so that it is not necessary to refer to record history information. Can be restored.
Furthermore, when data is linked, the update area data 133, the record access information data 134, and the entity management table data 135 that are not used at the time of restoration can be removed, so that the disk area for storing the backup file 10 can be saved.

It is a block diagram which shows the data management apparatus by Embodiment 1 of this invention. It is explanatory drawing which shows the storage format of the data in a data storage area. It is explanatory drawing which shows the storage format of the data of an entity management table. It is a flowchart which shows the data registration process of a data management apparatus. It is a flowchart which shows the data deletion process of a data management apparatus. It is a flowchart which shows the data update process of a data management apparatus. It is a flowchart which shows the optimization process of a data management apparatus. It is explanatory drawing which shows backup start record information. It is a flowchart which shows the backup process of a data management apparatus. It is explanatory drawing which shows the structure of the backup file which a data management apparatus produces at the time of backup. It is a flowchart which shows the restore process of a data management apparatus. It is explanatory drawing which shows the storage format of the data in a backup file and a data storage area. It is a flowchart which shows the backup file connection process of a data management apparatus. It is explanatory drawing which shows a backup file.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Data management apparatus, 2 Application program, 3 Data management part (data management means), 4 Operation processing part (operation processing means), 5 Data access part, 6,138 Data storage area (data storage means), 7,145 Entity Management table, 8 Backup start record information, 9 Backup medium, 61, 139 Reference area, 62, 143 Update area, 63, 144 Record access information, 64, 140-142, 193-195 record, 65, 73, 82 Record number , 66 offset, 67 size, 71 total number of records, 72 reference area record number, 74 logical ID, 75 deletion flag, 81 backup type, 101, 121, 126, 131, 151, 157, 163, 181 creation date, 102, 122, 127, 132, 52, 158, 164, 182 Reference area start record number, 103, 123, 128, 133, 153, 159, 165, 183 Reference area end record number, 104, 184 Reference area data offset, 105, 154, 160, 166 185 Reference area data size, 106,186 Update area data offset, 107,167,187 Update area data size, 108,188 Record access information data offset, 109,168,189 Record access information data size, 110,190 Entity management table Data offset, 111, 169, 191 Entity management table data size, 112, 124, 129, 134, 155, 161, 170, 192 Reference area data, 113, 135, 171, 196 Update area Data, 114, 136, 172, 197 Record access information data, 115, 137, 173, 198 Entity management table data, 120, 150 Backup file A, 125, 156 Backup file B, 130, 162 Backup file C, 180 Backup file D.

Claims (5)

A data storage means comprising an update area in which data addition is permitted and a reference area in which only data reference is permitted;
Information storage means for storing entity management information for managing the end of the reference area of the data storage means and backup start data information for specifying the beginning of the backup target of the reference area of the data storage means;
Based on the entity management information, the data stored in the update area of the data storage means is added to the reference area, the data added to the reference area is deleted from the update area, and the data in the data storage means is deleted. Data management means for updating the entity management information in response to the change;
The data specified based on the backup start data information and the entity management information acquired from the reference area stored in said data storage means, all data of the specified data and the update area of the reference area, the A data management apparatus comprising operation processing means for performing backup processing on the entity management information stored in the information storage means. The backup start data information has differential backup start data information,
Operation processing means
Based on the differential backup start data information, differential backup processing is performed for the data specified in the reference area stored in the data storage means and all the data in the update area, and the entity management information stored in the information storage means. The data management apparatus according to claim 1, wherein the differential backup start data information is updated according to a full backup process. Incremental backup start data information is included in the backup start data information.
Operation processing means
Based on the incremental backup start data information, an incremental backup process is performed for the data specified in the reference area stored in the data storage means and all the data in the update area, and the entity management information stored in the information storage means. 2. The data management apparatus according to claim 1, wherein the data management apparatus updates the incremental backup start data information according to a full backup process, a differential backup process, or an incremental backup process. Operation processing means
2. The reference area data that has been backed up and the data that has been updated by the latest backup process are restored to the data storage means, and the entity management information from the latest backup process is restored to the information storage means. The data management device according to any one of claims 1 to 3. Operation processing means
A backup data is created by concatenating each data in a reference area that has been backed up multiple times, data in an updated area by the latest backup process, and entity management information by the latest backup process. The data management device according to any one of claims 1 to 3.

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