JPH08249222A - Method and device for checking data base consistency - Google Patents

Abstract

PURPOSE: To provide a method and device for checking data base consistency capable of accurately checking the consistency of a data base without stopping an on-line processing. CONSTITUTION: While applying reference locking so as to control the access of other processings to the combination of fields or the field of a checking object by an exclusive control means (steps S21-S23), the consistency of the combination of fields or a field of the checking object is checked, the checking processing is repeated for all the fields or combination of the fields of the data base (the step S28) and thus, the consistency of the entire data base is checked.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a database consistency check method and apparatus for checking the consistency of a database without interrupting online processing of the database.

[0002]

2. Description of the Related Art A database may be destroyed because its storage structure is broken or the correspondence between a plurality of fields becomes defective. Therefore, the consistency check, that is, the database is not destroyed. It is necessary to check whether or not it is appropriate.

The database consistency check is to check the storage structure of the database in order to find abnormalities in the validity of various fields. The contents of the database consistency check include a single field (directory / directory). Format check to check the correctness of the setting values of the schema, table, and index fields, and between multiple fields (directory-
There is a correlation check for checking whether the correspondence relationship between schemas, indexes-records, etc.) is set correctly.

Since these fields are updated from the online processing, there is a state where the consistency of the fields cannot be guaranteed during the online processing. Therefore, conventionally, the online processing is stopped when the consistency check is performed on the entire database, and the check is performed in a state where the contents of the check target field do not change.

[0005]

As described above, in the conventional database consistency check, it is necessary to stop the online processing, and it is not possible to realize a database system that realizes online processing without interruption. There is.

The present invention has been made in view of the above,
An object of the present invention is to provide a database consistency check method and apparatus capable of appropriately checking the consistency of a database without stopping online processing.

[0007]

In order to achieve the above object, in the database consistency check method of the present invention, while a process is accessing a field which is a part of the database in the database, other processes are the same. The exclusive control means for controlling not to access the database part and the checking means for checking the consistency of each field or each combination of fields are provided, and the access of other processing to the field or combination of fields to be checked is described above. By checking the consistency of the field or combination of fields to be checked with the exclusive control means, the checking means is used to check the consistency, and this check process is repeated for all fields or combinations of fields in the database. And summarized in that to check the entire database consistency.

Further, the database consistency check device of the present invention is a database consistency check device for checking the consistency of a database without interrupting the online processing of the database. Exclusive control means to prevent other processing from accessing the same database part while one process is accessing it, and check means to check the consistency of individual fields or combinations of individual fields. Check control for controlling the consistency of the field or combination of fields to be checked by the checking means while restricting the access of other processing to the field or combination of fields by the exclusive control means. And the step, and summarized in that and a repetition control means for controlling to perform repeated checking process by the checking control means so as to check the integrity of the entire database for the combinations of all the field or fields in a database.

[0009]

In the database consistency checking method and apparatus of the present invention, the exclusive control means regulates the access of other processing to the field or combination of fields to be checked, and the consistency of the field or combination of fields to be checked. Is checked by the check means, and the consistency of the entire database is checked by repeating this check process for all fields or combinations of fields in the database.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an explanatory diagram when the database consistency checking method according to an embodiment of the present invention is applied to a correlation check between an index and a record. In the figure, 11 is a record, 12 is an index, 13 is an index node, 14 is a leaf node, and 15 is a root index node.

Next, an example of checking the existence of an index corresponding to a record in FIG. 1 will be described with reference to the flowchart shown in FIG.

In FIG. 2, first, a reference lock is applied to the record 11 to be checked so that no other process accesses the record (step S2).
1). The root index node 15 is reference-locked and the lower index node is searched (step S22). then,
The searched index node is reference locked, the upper index node is unlocked, and the lower index node is searched (step S23). Then, it is determined whether or not the index node at the bottom is reached (step S24). If the index node at the bottom is not reached, the process returns to step S23, and the same process is repeated until the index node at the bottom is reached. .

If the index node at the bottom is reached, the leaf node 14 is searched (step S2).
5) Check the existence of the record identifier RID that points to the record to be checked (step S2)
6). The presence of the record identifier RID means that the correlation of the index with respect to the record is good.

Then, the index node and the record at the bottom are unlocked (step S27), thereby completing the check of the target record.

Next, it is judged whether or not the check processing has been completed for all the records (step S28), and if not completed, the processing returns to step S21 and the above processing is repeated until all the records are completed. To do.

In step S21, S22, S23, if the lock conflicts with other processing, the target record is not checked (lock is released).

Next, an example of checking the existence of the record corresponding to the index will be described with reference to the flowchart shown in FIG.

In FIG. 3, first, the root index node is reference locked and the lower index node is searched (step S31). Then, the searched index node is reference-locked, the upper index node is unlocked, and the lower index node is searched (step S32). And
It is determined whether or not the index node at the bottom is reached (step S33). If the index node at the bottom is not reached, the process returns to step S32 and the same process is repeated until the index node at the bottom is reached.

When the index node at the bottom is reached, the record identifier RID is obtained from within the leaf node (step S34). Then, the record pointed to by the record identifier RID in this leaf node is reference-locked (step S35), and the existence of the record is checked (step S36). Then, the record and the lowest index node are unlocked, thereby completing the check of the target record (step S37).

Next, it is judged whether or not the check processing has been completed for all records (step S38), and if not completed, the processing returns to step S31, and the above processing is repeated until it is completed for all records. To do.

In steps S31, S32, and S35, if the lock conflicts with another process, the target record is not checked (unlocked).

[0023]

As described above, according to the present invention,
While the exclusive control means regulates the access of other processing to the field or combination of fields to be checked, the consistency of the field or combination of fields to be checked is checked by the checking means, and this check processing is performed on all the databases. Since the consistency of the entire database is checked by repeatedly performing the field or the combination of fields, the consistency check of the database can be appropriately performed without stopping the online processing. Note that the lock period that regulates access to other processes is about the same as the transaction associated with index update, so the effects of conflicting database integrity check processes and online processes (decrease in concurrency) are that online processes compete with each other. This is about the same as in the case, and therefore, the consistency of the entire database can be accurately checked in a state where the database contents change momentarily without stopping the online processing.

[Brief description of drawings]

FIG. 1 is an explanatory diagram when a database consistency check method according to an embodiment of the present invention is applied to a correlation check between an index and a record.

FIG. 2 is a flowchart showing a process for checking the existence of an index corresponding to a record.

FIG. 3 is a flowchart showing a process for checking the existence of a record corresponding to an index.

[Explanation of symbols]

 11 record 12 index 13 index node 14 leaf node 15 root index node

Claims (2)

[Claims] 1. An exclusive control means for controlling, while a process is accessing a field which is a part of a database in a database, another process not to access the same database part, and an individual field or an individual field. The check means for checking the consistency of the combination of is checked, while the access of other processing to the field to be checked or the combination of fields is restricted by the exclusive control means, the consistency of the field to be checked or the combination of fields is checked. A database consistency check method characterized in that the consistency of the entire database is checked by repeating the checking process by all the fields or combinations of fields in the database. 2. A database consistency check device for checking the consistency of a database without interrupting online processing of the database, wherein during a process is accessing a field which is a part of the database in the database, Exclusive control means to prevent other operations from accessing the same database part, checking means to check the consistency of individual fields or combinations of individual fields, and other operations on the field or combination of fields to be checked Checking the consistency of the field or combination of fields to be checked by the checking means while restricting the access by the exclusive control means, and checking the consistency of the entire database. Ku the check control unit database consistency check device characterized by having a repeating control means for controlling to perform repeated for the checking process combination of any field or fields in a database by.