JP2001014336A - Database system and its control method, and computer- readable recording medium where the control program is recorded - Google Patents

Abstract

PROBLEM TO BE SOLVED: To keep the optimum balance of a database, which synchronizes information among multiple information storage devices, as to an error in the synchronism and the load on facilities. SOLUTION: A document editing device performs an indexed process 21 and adjusts time intervals (reflection interval 23) where rewriting to a document file group 2 is reflected intermittently on an index 12 according to a specific condition. As the condition, the rate (nonreflection rate) at which the rewriting to the document file group 2 is not reflected on the index 12 is used. Thus, the period of reflection is automatically controlled to synchronize the document file group 2 with the index 12 while preventing the facilities from being overloaded owing to an overfrequency and information precision from decreasing owing to a underfrequency.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a database system for synchronizing information among a plurality of information storage devices, a control method therefor, and a computer-readable recording medium storing the control program.

[0002]

2. Description of the Related Art In a document search system including a document group and a document search index, or in a distributed database system including an original and a copy thereof, the contents are synchronized between a plurality of information storage devices storing data. Need to be synchronized.

[0003] Here, the following four conventional examples will be given as to a method of repeatedly rewriting rewriting to one information storage device to another information storage device.

[Prior Art 1] There is a method of creating index data for search in advance in order to speed up the search of a document group (Japanese Patent Laid-Open No. 5-61).
No. 910 (publication date: March 12, 1993)
Day) and others). In this case, when a new document is added or an existing document is modified or deleted, it is necessary to reflect that in the index. That is, it is necessary to recreate the index partially or entirely.

FIG. 10 shows an example of a DFD (data flow diagram) of a document editing apparatus to which the above method is applied.

Here, the notation method of DFD will be described. The ellipse is called a process and represents a transformation of the data.
A process has one or more inputs and one or more outputs. It should be noted that the term process refers to a running program in certain computer systems, but is used in this specification in the above sense. The rectangle is called an actor and actively drives the flow of data by producing or consuming data. The two horizontal parallel lines are called a data store and respond to any data storage and access requests. The input of the data store means storage of data, and the output means access. Note that the data store itself does not operate spontaneously. Solid arrows represent data flows (data flows), processes,
Actors, data store input and output. A broken arrow is called a control flow, and indicates that the calculation result of a certain process determines whether or not to calculate another process. However, the DFD expresses the data flow and calculation specifications, and the control flow and the order of operations are not the main ones.

Hereinafter, the document editing apparatus will be described with reference to FIG. The document editing device creates a document, stores the created document, and prints the created document according to a user operation. You can also search, print, modify,
And delete. A full-text search is performed at high speed using the index method for searching documents.

[0008] The document editing apparatus periodically reflects the rewriting (new, modified, and deleted) of the document file group in the index. The user sets the interval of the reflection processing. The reflection process includes a process of scanning a document file group and searching for a document that has not been reflected in the index. Here, a document that has not been reflected is a document that has been newly created, modified, or deleted since the previous reflection processing.

The terminal 51 is a terminal device for a user.
The terminal 51 performs creation, correction, deletion, printing, and retrieval of a document. The terminal 51 includes a keyboard input device, a screen display device, and a printing device (printer).

The document file group 52 is an accumulation of document files created by the user. The document file group 52 is to be corrected, deleted, printed, and searched.

The document editing process 54 edits a document according to a user operation. The document editing process 54
Create, modify, delete, and print documents.

The document retrieval process 56 retrieves a document according to the operation of the user. The document search process 56
A document matching the search condition given by the user from the terminal 51 is searched from the index 62, and if found, the corresponding document is read from the document file group 52, and the corresponding portion is displayed on the screen of the terminal 51 and shown to the user.

The index 62 is used for searching.
This is search index data for realizing high-speed search.

An indexing process 71 creates an index 62 based on the document file group 52. The indexing process 71 includes creating a new document file,
If there are corrections and deletions, they are reflected in the index 62.

The last reflection time 72 is the time at which the execution of the indexing process 71 was last started. The last reflection time 72 is updated each time the indexing process 71 is started.

The reflection interval 73 is a value representing a time interval in which the indexing process 71 is to be executed, in minutes. The reflection interval 73 indicates that the user
1 can be changed.

The time comparison process 74 compares the time elapsed from the last reflection time 72 to the present with the reflection interval 73. If the former is not smaller than the latter, the indexing process 71 is started.

[Conventional Example 2] A case in which a company having a plurality of factories mutually enters a supplier DB (database) managed by each factory with reference to FIGS. 11 and 12 will be described. FIG. 11 is a DFD showing the configuration of the supplier DB system, but in order to avoid complication, the terminal 81 is illustrated only in the Sapporo factory Bn. Actually, as shown in FIG. 12, the terminal factory 81 is also provided at the head office factory H and the Kobe factory Bs.

The supplier DB 82 of each factory Bn, Bs stores the name of the supplier, the area code, the contact information, the part code of the handled item, the unit price, and the standard delivery date. Usually, local suppliers are often searched in the supplier DB 82 in the own factory premises, but the supplier DBs 82 in other factories can also be searched.

A general table of contents 84 is provided for the convenience of a wide area search including the supplier DB 82 of another factory. That is, the factories Bn and Bs periodically transmit data that summarizes the names, region codes, and part codes of the respective suppliers to the head office factory H.
Send to In the head office factory H, data from each factory Bn and Bs is synthesized by the synthesis process 83, a factory code is added, and a total table of contents 84 is created. The total table of contents 84 is transmitted from the head office factory H to each factory Bn, Bs, and each factory Bn, Bs,
The same copy is placed on Bs.

The wide area search is performed according to the following procedure. First, the total table of contents 84 is searched by a part code, and a supplier who handles the part,
Get the factory code. Then, the supplier DB 82 of the factory indicated by the factory code is remotely searched to obtain detailed information.

[Prior Art 3] An electronic telephone directory system for sharing electronic telephone directory data between head offices connected by a low-speed line will be described with reference to FIGS. FIG.
Reference numeral 3 denotes a DFD indicating the configuration of the electronic telephone directory system. The function of searching the DB of another store when the DB is stopped is shown in FIG. 14 to avoid complication.

First, the electronic telephone directory 92 is installed in the head office H, and each branch Bn, Bs can communicate with the head office H every time a search is performed. However, searching via a low-speed line is often too slow and inconvenient. Therefore, an electronic telephone directory (copy) 96 which is a copy of the electronic telephone directory (original) 92 placed in the head office H needs to be placed in each of the branches Bn and Bs. In this way, the search in normal times can be performed only via the high-speed local line of the shop. Only when the electronic telephone directory (replica) 96 in the own store is stopped due to a failure or maintenance work, the electronic telephone directories 92 and 96 in other stores can be searched.

In this case, in order to maintain data consistency between the head office and branch office, the head office H manages the original of the electronic telephone directory DB and changes the data by each branch Bn and Bs (change process 94).
Is performed by each branch Bn, Bs requesting the head office H (change request 93). Therefore, the DB of the electronic telephone directory (original) 92 of the head office H has an update function. The change request 93 from the head office H and each of the branches Bn and Bs is reflected in the electronic telephone directory (original) 92 of the head office H as needed. The DB of the electronic telephone directory (replication) 96 of each branch Bn, Bs is a simple type and can only be searched. Therefore, regular branch DB
It is necessary to stop the (electronic telephone directory (replica) 96) and copy the contents of the head office DB (electronic telephone directory (original) 92).

[Prior Art 4] An electronic telephone directory system for sharing electronic telephone directory data between head offices connected by a low-speed line will be described with reference to FIGS. 15 and 14. -149308 (publication date:
1998 (June 2, 1998) ") and others). FIG.
Is a DFD showing the configuration of the above electronic telephone directory system.
The function of searching the DB of another store when the DB is stopped is shown in FIG. 14 to avoid complication.

The electronic telephone directory system of the present prior art is similar to the electronic telephone directory system of the conventional example 3, but the DBs (electronic telephone directories 97) of the branches Bn and Bs are also stored in the DB of the head office H.
The difference is that it has an update function as well.

That is, the update by each branch Bn, Bs does not request the head office H, but updates the electronic telephone directory 97 in the own office. Then, the head office H and the D of each branch Bn, Bs
B (electronic telephone directory 97) regularly exchanges data by a synchronization process 98 to synchronize data, thereby maintaining data consistency between head offices.

[0028]

In the above-mentioned conventional examples 1 to 4, additional information storage devices, that is, an index, a total table of contents, and a replica are introduced.
Its purpose is to speed up the search. In addition, in the example of copying the electronic telephone directory, it becomes possible to search even while the DB is stopped,
It has also helped increase availability.

However, the above-mentioned conventional examples 1 to 4
In such a case, it is important to determine the timing of synchronizing the contents between the information storage devices. If it is extremely important to have the same content without any inconsistency, the rewrite needs to be reflected immediately. For example, rewriting a document (adding a new document, modifying / deleting an existing document)
If there is, reindex it immediately. Or,
If there is a change in the electronic telephone directory data, the change is immediately distributed. However, appropriate equipment reinforcement (high-speed indexer, high-speed line) is required.

In such applications, some errors are often tolerated. Then, the reflection processing is periodically executed. Here, a good effect cannot be obtained unless the time interval of the reflection processing is appropriately adjusted according to the use or the load state of the equipment.

That is, if the frequency of reflection is too low, the probability of reading information that is not the latest is increased. As long as the reflection process is performed asynchronously with respect to reading and writing of information, such an error is essentially unavoidable. Therefore, it is necessary to consider that the error rate does not increase. The reason why such an error rate becomes large is that the frequency of reflection is too low, and that an error generated between the information storage devices becomes excessive.

Conversely, if the frequency of reflection is too high, the load on the equipment (apparatus and line) will be increased unnecessarily, and the capacity of the equipment will be wasted. In particular, when there is not a small amount of information that is corrected little by little or information that exists only temporarily, waste increases. As a result, the original task of reading and writing information is rather slowed down. In the case of an electronic telephone directory, the DB is stopped more than necessary. this is,
This is contrary to the purpose of speeding up retrieval of documents and DBs.

As described above, the optimum reflection frequency for performing the reflection process needs to be appropriately adjusted according to the use and the load state of the equipment. However, the optimal reflection frequency changes depending on the frequency of rewriting information. Therefore, in order to increase the effect of introducing the additional information storage device, the reflection frequency must be continuously adjusted appropriately.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a database system for synchronizing information among a plurality of information storage devices, in which a synchronization error and a facility load are imposed. An object of the present invention is to provide a database system capable of maintaining an optimal balance, a control method thereof, and a computer-readable recording medium recording the control program.

[0035]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a database system according to the present invention comprises a first information storage device, a second information storage device, and a first information storage device. Reflecting means for intermittently reflecting the change made on the second information storage device; and reflecting the change in accordance with the degree of error between the contents of the first information storage device and the contents of the second information storage device. And reflection control means for controlling activation of the means.

In order to solve the above-mentioned problems, a method for controlling a database system according to the present invention is a method for controlling a database system including a first information storage device and a second information storage device, A reflection process for intermittently reflecting a change made to the first information storage device to the second information storage device; and a reflection process between the contents of the first information storage device and the contents of the second information storage device. And a reflection control process for controlling activation of the reflection process according to the degree of the error.

According to another aspect of the present invention, there is provided a computer-readable recording medium for controlling a database system including a first information storage device and a second information storage device. A computer-readable recording medium on which a program is recorded, wherein a reflection process for intermittently reflecting a change made to a first information storage device to a second information storage device; A program for causing a computer to execute a reflection control process for controlling activation of the reflection process in accordance with the degree of error between the content of the device and the content of the second information storage device is recorded. And

According to each of the above structures, for example, in the document search system, the information to be searched is stored in the first information storage device.
Information (index) for search assistance is stored in the second information storage device. For example, in a distributed database system, original information is stored in a first information storage device, and duplicate information is stored in a second information storage device. In the database system, a change made to a part of the information storage devices (first information storage device) in the plurality of information storage devices is repeated to another information storage device (second information storage device). By reflecting, the consistency of the information of the entire database system is ensured.

Here, in the above database system,
By the reflection control process, the activation of the reflection process is controlled according to the degree of error (unreflection rate) between the content of the first information storage device and the content of the second information storage device. For example, when the non-reflection ratio exceeds the reference value, the reflection process can be started, and the update performed on the first information storage device can be reflected on the second information storage device.

As described above, in the above database system, when the load for calculating the unreflected ratio is almost negligible compared with the load for the reflection process, it is possible to directly and simply automatically control the activation of the reflection process. it can. That is, in a database system that allows a certain error between a plurality of information storage devices (databases and the like) and allows the contents to be the same, the timing of the reflection process is set by a manual operation of the user or a simple fixed time interval. Instead, by dynamically controlling according to the situation, it is possible to optimally maintain a balance between two conflicting factors, namely, the identity of information and the load on the device.

In order to solve the above-mentioned problems, the database system of the present invention further comprises:
A reflection interval setting unit that sets a reflection interval for intermittently activating the reflection unit based on a degree of an error between the content of the first information storage device and the content of the second information storage device. Features.

In order to solve the above-mentioned problem, the control method of the database system according to the present invention further comprises the step of controlling the reflection by processing the contents of the first information storage device and the contents of the second information storage device. And a reflection interval setting process for setting a reflection interval for intermittently starting the reflection process based on the degree of the error.

The computer-readable recording medium of the present invention further comprises:
The program sets a reflection interval at which the reflection control process intermittently activates the reflection process based on a degree of error between the content of the first information storage device and the content of the second information storage device. It is characterized by including a reflection interval setting process.

According to each of the above configurations, further, in the above-mentioned database system, the first processing is performed by the reflection interval setting processing.
A reflection interval is set according to the degree of error (unreflection rate) between the content of the information storage device and the content of the second information storage device, and control is performed so that the reflection process is started at each reflection interval. Becomes possible. For example, based on a comparison result obtained by comparing the non-reflection rate and the reference value, the operation can be performed while appropriately adjusting the reflection interval for starting the reflection processing.

As described above, in the database system, when the load for calculating the non-reflection rate cannot be ignored compared with the load for the reflection processing, the reflection timing is automatically controlled by an indirect method of adjusting the reflection interval. be able to. That is, a plurality of information storage devices (databases, etc.)
In a database system that allows a certain amount of error between groups and makes the contents the same, the timing of the reflection process is dynamically controlled according to the situation instead of being manually operated by the user or a simple fixed time interval By doing so, it is possible to optimally maintain the balance between the two contradictory elements of information identity and device load, while preventing overload on equipment due to excessive frequency and reduction in information accuracy due to infrequent frequency.

[0046]

DESCRIPTION OF THE PREFERRED EMBODIMENTS [Embodiment 1] One embodiment of the present invention will be described with reference to FIGS.
It is as follows.

This embodiment is an example in which the database system according to the present invention is applied to a document editing device having a document search function. This embodiment is based on the conventional example 1.
This corresponds to an application example to the device described in. Further, the present embodiment can be similarly applied to the supplier DB described in the conventional example 2.

The document editing apparatus creates a document according to a user operation, and stores and prints the created document. Also, search, print, modify, and delete created documents. A full-text search is performed at high speed using the index method for searching documents.

In this embodiment, rewriting (new, modification, and deletion) of a document file group is performed in the same manner as in Conventional Example 1.
Reflect in the index repeatedly. It is a feature of the document editing apparatus that the interval of the reflection processing is automatically adjusted.

Here, the reflection process includes a process of scanning a document file group and searching for a document that has not been reflected in the index. An unreflected document is a document newly created, modified, or deleted after the previous reflection process.

In this case, if the interval is too short, the waste is
This is the load of scanning the document file group to search for unreflected documents. Then, the document editing apparatus according to the present embodiment can maintain the quality of the search while preventing this waste.

FIG. 1 is a data flow diagram (DFD) showing an outline of functions of the document editing apparatus according to the present embodiment.
The notation of DFD is as described in the above-mentioned conventional example 1.

The document editing device includes a terminal 1 as an actor, a document file group (first information storage device) 2 as a data store, and an index (second information storage device) 1
2. Last reflection time 22, reflection interval 23, unreflected ratio reference 26, document editing process 4, document retrieval process 6, indexing process (reflection means,
Reflection process) 21, time comparison process (reflection control means,
(Reflection control process) 24, a reflection interval adjustment process (reflection interval setting means, reflection interval setting process) 25, and a non-reflection rate calculation process 27.

The terminal 1, which is an actor, is a terminal device for a user, and includes a keyboard input device, a screen display device,
And a printing device (printer). The terminal 1 creates, modifies, deletes, prints, and searches for a document.

Next, each data store will be described.

The document file group 2 is an information storage device that stores a document file created by a user.
Can be deleted, printed, and searched. Further, the document file group 2 is an object to reflect the contents.

The index 12 is search index data used at the time of a search and for realizing a high-speed search.

The last reflection time 22 is a time at which the reflection by the indexing process 21 (described later) is executed last. The last reflection time 22 is updated and stored each time the indexing process 21 is started.

The reflection interval 23 is a time interval at which the indexing process 21 is to be executed, and is a minute.
Expressed in units. The reflection interval 23 is updated each time it is set by the reflection interval adjustment process 25 (described later).
It is memorized.

The non-reflection rate reference 26 gives a reference value for adjusting the reflection interval (frequency) in the reflection interval adjustment process 25 (described later). The non-reflection rate reference 26 is input and adjusted by the user from the terminal 1 and stored.

Next, each process will be described.

The document editing process 4 edits the document according to the user's operation and rewrites the contents of the document file group 2. Specifically, the document editing process 4 creates, modifies, deletes, and prints the document.

The document retrieval process 6 retrieves a document (information) from the document file group 2 according to a user operation. Specifically, the user searches the index 12 for a document that matches the search condition given from the terminal 1. If it is found in the index 12, the document file group 2
And reads the relevant document from the terminal 1, and displays the relevant part on the screen of the terminal 1 to show the user.

The indexing process 21 reflects the rewriting performed on the document file group 2 on the index 12. That is, the indexing process 2
1 creates an index 12 based on the document file group 2. Specifically, the indexing process 21
If a new creation, modification, or deletion of a document file is performed, that is reflected in the index 12. In the document editing apparatus, the time interval for starting the indexing process 21 is automatically adjusted.

The time comparison process 24 compares the time elapsed from the last reflection time 22 to the present with the reflection interval 23, and starts the indexing process 21 if the former is not smaller than the latter.

The reflection interval adjustment process 25 adjusts the reflection interval 23 by comparing the unreflected ratio with a reference value. The reflection interval adjustment process 25 will be described later in detail with reference to FIG. 2, and includes the following three internal processes. That is, the reflection interval adjustment process 25 includes an internal process for comparing the unreflected ratio with the reference value, an internal process for increasing the reflected interval 23 when the unreflected ratio is too small, and an internal process for increasing the reflected interval 23 when the unreflected ratio is excessive.
And reducing internal processing.

The unreflected ratio calculation process 27 calculates or estimates the current unreflected ratio and feeds it back.
That is, the non-reflection rate calculation process 27 obtains a non-reflection rate indicating an index error and feeds it back every time the indexing process 21 is performed.

Here, the indexing process 21
A document that has not been reflected in the index 12 is found, and the document is processed. Therefore, the number of unreflected documents is obtained during the indexing process 21. Therefore, the document editing apparatus may configure the unreflected ratio calculation process 27 as an internal process of the indexing process 21.

Further, in the indexing process 21, a process 27 for calculating the unreflected ratio and a process 25 for adjusting the reflection interval are also performed. The more frequently the process of calculating the non-reflection ratio 27 and the process of adjusting the reflection interval 25 are performed, the more the accuracy of the reflection interval is improved. However, in the document editing apparatus, the process 27 for calculating the unreflected ratio and the process 25 for adjusting the reflection interval are performed by the indexing process 21
Only when you do. Because, in the above document editing device,
This is because the load increased by increasing the frequency of the unreflected ratio calculation process 27 is almost equal to the load increased by increasing the frequency of the indexing process 21.

The procedure of the reflection interval adjustment process 25 will be described with reference to the flowchart of FIG. Note that the arithmetic expression in each step in the flowchart is an example, and the present invention is not limited to this.

The characteristics of the procedure of the reflection interval adjustment process 25 are the following two. First, keep the quality at or above the standard. Second, since the unreflected ratio fluctuates, care should be taken not to be greatly affected by temporary waves.
For this reason, we take care of excess quality and gradually reduce the quality. Conversely, for quality defects,
Improve quality quickly, but prepare a mechanism that can be restored.

In step S11, an excessive error is detected. That is, a quality defect and an excessive reflection interval 23 are detected. If the non-reflection rate is larger than the reference (YES), the process proceeds to step S16 to reduce the reflection interval 23 in order to restore the quality. Specifically, the non-reflection rate (error) is considered to be proportional to the reflection interval 23, and the adjustment is performed by the ratio between the non-reflection rate and its reference. That is, if the non-reflection rate is F times the reference, the reflection interval 23 is set to 1 / F.

In steps S21 and S25, conversely,
Detects an error that is too small. That is, excessive quality and an excessively small reflection interval are detected. Then, steps S21, S25,
In S22, the excess quality is divided into three ranks, and different formulas are applied to extend the reflection interval.

If the determinations in steps S11, S21, and S25 are all NO, it is determined that the quality is within the appropriate range, and the reflection interval 23 is maintained. In the flowchart of FIG. 2, the unreflected ratio is 0.7
This is the case within the range of 5 to 1.0.

Here, a description will be given of the excessive quality treatment. If the quality is suddenly reduced in response to a temporary phenomenon, there is a risk that the next time a large defect will occur. Therefore, the adjustment is performed in a smaller range than when a quality defect is detected.

Basically, the greater the degree of excess quality, the greater the quality is reduced. However, the inclination is made gentler than at the time of the quality defect (S26). In the flowchart of FIG. 2, the reference ratio, which is the ratio of the non-reflection rate to the reference value, is F (the non-reflection rate is F times the reference), and the reflection interval 23 is multiplied by (1 / F) at the time of a defect (S16). . On the other hand, when the quality is excessive, (3 / 8F) +
(1/2) (S26). However, the maximum is twice (S21, S24). Thus, by temporarily reducing the quality, it is possible to cope with a temporary wave.

On the other hand, if the quality is excessively increased by the temporary wave, the restoration is accelerated (S22, S23). When the reference ratio F is equal to or less than a quarter and the previous reference ratio F is equal to or greater than 4, it is highly likely that the previous defect was transient. Therefore, the reflection interval 23 that has been reduced too much is returned to half of the previous time. In other words, with caution, we do not restore at once, but only to accelerate recovery.

As shown in FIG. 1, the document editing apparatus performs the reflection interval adjustment process 25 only at the time of performing the reflection process (indexing process 21).
Steps S12 and S13 as in Embodiment 3 (FIG. 8)
Is not required.

Here, the arithmetic expressions of the above steps will be described.

(1) Appropriate range of quality As described above, the appropriate range of quality is set to 0.75 ≦ F ≦ 1.0
Is set to If the appropriate lower limit of quality is too close to 1.0, the reflection interval tends to fluctuate, and the unreflected ratio cannot be correctly obtained. Conversely, if the lower limit of the appropriate quality is set too low, the control is weakened and the quality tends to be excessive, so that the load on the apparatus increases. Therefore, it is necessary to set the appropriate lower limit of quality to an appropriate value such that the reflection interval does not fluctuate. Therefore, in the present embodiment, the appropriate lower limit of quality is set to 0.75.

(2) Coefficient at Defect As described above, when a defect of quality occurs, the coefficient (1
/ F) is multiplied by the reflection interval. As a result, it can be expected that the unreflected ratio after the next time will be about 1. When importance is attached to prevention of defects, the coefficient may be set to, for example, (0.9 / F). However, if the coefficient is excessively small (strict adjustment), the reflection interval is likely to fluctuate.

(3) Coefficient at the time of excessive quality As described above, at the time of excessive quality, the coefficient (3 / 8F) +
(1/2) is multiplied by the reflection interval. However, this coefficient is 2
Is the upper limit. This coefficient is adjusted more slowly than the coefficient (1 / F) at the time of the defect, that is, the coefficient is made closer to 1. Further, when the coefficient is regarded as a function of (1 / F), the function is not discontinuous. That is, the adjustment is stabilized while avoiding the discontinuous function. in this way,
Relaxing the adjustment and setting an upper limit on the coefficient are both effective as measures against temporary waves.

(4) Degree of Acceleration of Recovery When the recovery is accelerated as described above, the reflection interval becomes twice or more. The lower limit value of 2 and the upper limit value 2 of the coefficient at the time of excessive quality are intentionally made to coincide with each other in order to stabilize the adjustment. The reason for adopting a value that is 0.5 times that of the previous reflection interval instead of using the previous reflection interval as it is is that, with caution, recovery is not performed at once, but only to accelerate recovery. It should be noted that since only the recovery is accelerated, the expected value of F is only 0.5, and there is a possibility that F <0.75. In that case, it is treated as normal excess quality.

As described above, the database system according to the present embodiment generates search assistance information to facilitate the search for one or more information storage devices, The rewriting stored in the information storage device described above and performed on the information storage device to be searched is intermittently reflected in information for search assistance, and the timing of the reflection process is automatically controlled.

Further, the database system according to the present embodiment calculates or estimates the degree of an error occurring between the information storage device groups due to intermittent reflection processing, and obtains the calculated error at least once in the past. Is used as an index for controlling the timing.

Further, the database system according to the present embodiment calculates or estimates the ratio of the contents stored in a certain information storage device whose rewrite has not yet been reflected in another information storage device, and stores the information. The above ratio is used as an index indicating an error generated between the device groups.

In addition, the database system according to the present embodiment calculates or estimates the ratio of the content stored in one information storage device that has not yet been rewritten to another information storage device and feeds it back. The above processing is performed.

Therefore, the document editing apparatus according to the present embodiment automatically controls the time of reflection from the document group to the index. That is, the document editing device reflects the data by a predetermined condition or calculation (indexing process 21).
, The reflection is started when the predetermined condition is satisfied, or the reflection is not started when the predetermined condition is not satisfied. The conditions include, for example, the unreflected ratio, that is, the document file group 2
Is used, the ratio of which is not reflected in the index 12 is used.

Therefore, by automatically controlling the time of reflection as described above, overload on equipment due to excessive frequency,
Rewriting to the document file group 2 can be intermittently reflected in the index 12 while preventing a decrease in information accuracy due to an underfrequency.

The document editing apparatus can also be applied to the apparatus of the conventional example 2 for automatic control of the timing of reflection from the supplier DB to the total table of contents.

In the document editing apparatus, the reflection process (the indexing process 21) performs the non-reflection rate calculation process 27 independently of the rewriting of the original (document file group 2).
Drive. Then, the document editing apparatus adjusts the reflection interval 23 for starting the reflection processing (indexing process 21) based on the comparison result obtained by comparing the current unreflected rate with the reference value.

That is, in the above document editing apparatus, since the load for calculating the unreflected ratio cannot be ignored compared with the load for the reflection processing, automatic control of the reflection timing is realized by an indirect method of adjusting the reflection interval. ing.

[Second Embodiment] The following will describe another embodiment of the present invention with reference to FIGS. For convenience of explanation, the first embodiment is described.
Members having the same functions as the members shown in are denoted by the same reference numerals, and description thereof will be omitted.

This embodiment is an example in which the database system according to the present invention is applied to an electronic telephone directory system extending between head offices. This embodiment corresponds to an application example to the device described in the conventional example 3. Therefore, the entire configuration is the same as that of the device of the conventional example 3.

FIGS. 5 and 6 are DFDs showing the entire configuration of the electronic telephone directory system according to the present embodiment. The notation of DFD is as described in the above-mentioned conventional example 1.

As shown in FIG. 5, the electronic telephone directory system comprises a head office H and branches Bn and B connected by a low-speed line.
s is a database system (equipment) for sharing electronic telephone directory data. Here, the electronic telephone directory system has a low line speed and is not suitable for interactive remote search.
e) A branch DB 12 ', which is a copy of 2', is placed. And
The normal search is performed only for the DBs 2 'and 12' of the own shop via only the high-speed local line. Then, only when the DB in the own store is stopped due to a failure or maintenance work, the DB of another store is searched (FIG. 6). In FIG. 6, the branch DB1
This shows a state where the branch terminal 11 of the north branch Bn is searching the head office DB 2 'and the branch DB 12' of the south branch Bs when 2 'is stopped.

Here, in the present embodiment, in order to maintain the consistency of the DB between the head office H and each branch Bn, Bs,
The head office H manages the original, and each branch Bn and Bs requests the head office H to change the DB. Therefore, head office H
The head office DB (electronic telephone directory DB) 2 'has an update function. And the change request from each branch Bn, Bs
At any time, it is reflected in the head office DB (first information storage device) 2 '. On the other hand, the branch DB (replica) of each branch Bn and Bs (second
Are simple types and do not have an update function. Therefore, it is necessary to appropriately stop the branch DBs 12 'and copy the contents of the head office DB 2'.

The outline of the duplication process 21 'is as follows. First, updating of the head office DB 2 'is prohibited, all data is read, and the prohibition of updating is released. Next, the read contents are distributed to each of the branches Bn and Bs. Each branch B
In n and Bs, when data reception is completed, the DB search service is stopped, the contents of the branch DBs 12 'are rewritten with the received data, and the search service is restarted after completion.

Here, if the interval of the duplication process (reflecting means, reflecting process) 21 'is too short, the load of reading all data from the head office DB 2', the line load distributed to each branch Bn, Bs, and the branch Bn, Uselessness such as service degradation for stopping Bs occurs. In this regard, the electronic telephone directory system can maintain the quality of the search while preventing such waste by automatically controlling the timing of the duplication process (processing) 21 '(described later).

Using the DFD shown in FIG. 3, the function of the electronic telephone directory system will be described in detail.

The electronic telephone directory system includes a head office terminal 1 ', a branch terminal 11 as an actor, a head office DB 2' as a data store, a change request 3, an update history 5, and a branch DB 1
2 ′, a reference 26 of the unreflected rate, a process of updating 4 ′, a duplication process 21 ′, a process 27 of calculating the unreflected rate, and a process of comparing the unreflected rate (reflection control means, reflection control processing) 28 It is comprised including.

First, each actor will be described.

The head office terminal 1 'is a terminal device for a user installed in the head office H. Head office terminal 1 'is head office DB
In addition to searching the electronic telephone directory DB 2 ', a change request for the head office DB 2' is issued. Therefore, the head office terminal 1 'is provided with a keyboard input device, a screen display device, and a printing device (printer).

The branch terminal 11 is a terminal device for a user installed in each of the branches Bn and Bs.
A request to change the (main store DB2 ') is issued. As shown in FIG. 6, the branch terminal 11 can remotely search the head office DB 2 'while the branch DB 12' is stopped.

Next, each data store will be described.

The head office DB 2 ′ is an electronic telephone directory DB installed in the head office H, and stores the original of the electronic telephone directory DB. The main store DB 2 ′ is mainly searched from the main store H. As shown in FIG. 6, while the branch DB 12 'is stopped,
The remote search may be performed from the branch terminal 11. The head office DB 2 'and the branch DB 12' are information storage devices whose contents are to be reflected.

[0107] The above change request 3 is issued from the main office terminal 1 'and the branch terminal 11 in the main office DB 2' (electronic telephone directory D).
B) is a change request (rewrite request).

The update history 5 is an accumulation of the history of the update processing performed by the update process 4 '. The update history 5 is used to calculate the unreflected rate in the unreflected rate calculation process 27. Note that the update history 5 is also used at the time of restoration from a failure in the head office DB 2 '.

The above-mentioned branch DB 12 ′ stores each branch Bn, Bs
Is an electronic telephone directory DB (duplicate) installed in the Internet. Branch DB
Reference numeral 12 'is a simple type having no update function, and can only search data. The creation and updating of data in the electronic telephone directory DB are performed at the head office H. Also, as shown in FIG.
The branch DB 12 'may be remotely searched from a terminal of another store while the DB of another store is stopped.

The non-reflection rate reference 26 provides a reference value for starting the duplication process 21 ′ in the non-reflection rate comparison process 28 (described later). The non-reflection rate reference 26 can be changed from the head office terminal 1 '.

Next, each process will be described.

The update process 4 'is performed in the head office DB 2'.
(Original) is updated. The update process 4 'is performed only at the head office H, and updates the head office DB 2' based on the change request 3 from the head office terminal 1 'and the branch terminal 11.

The copying process 21 'is performed in the head office DB 2'.
Is copied to the branch DB 12 '. Replication process 2
1 'is provided at the head office H, but is connected to the branch D via a line.
It includes a function to remotely control B12 '. Then, the electronic telephone directory system automatically controls the time when the copy process 21 'is started.

The procedure of the duplication process 21 'is as follows. First, update of the head office DB 2 'is prohibited, all data is read, and the update prohibition is released. Next, the read contents are distributed to each of the branches Bn and Bs. Each branch Bn, Bs
When the data reception is completed, the DB search service is stopped, the contents of the branch DB 12 'are replaced with the received data, and the search service is restarted.

In the non-reflection rate calculation process 27, the non-reflection rate indicating the error of the DB between the head office H and each of the branches Bn and Bs is periodically obtained and fed back.

In the non-reflection rate comparison process 28, the non-reflection rate is compared with a reference and the reflection by the replication process 21 'is started. Therefore, comparison process 2 of unreflected ratio
8 includes the following two internal processes. That is, the unreflected ratio comparison process 28 includes an internal process of comparing the current unreflected ratio obtained in the unreflected ratio calculation process 27 with the reference value of the unreflected ratio reference 26, Duplication process 2 if greater than the unreflected ratio criterion 26
1 'is started.

Here, the update process 4 ′ includes the change request 3
Is executed as needed based on That is, the DB search service is not stopped due to the update process 4 '. The update process 4 'sequentially processes the change requests 3 when the head office DB 2' is not being updated and is not in the update prohibited state. Note that the head office DB (original) 2 ′ is in an update prohibited state during the operation of the copy process 21 ′ and when the load is high.

The update process 4 'determines whether or not to suspend when one change request 3 has been processed. First, when there is no unprocessed change request 3, the update process 4 'is suspended after starting the process 27 for calculating the unreflected ratio. When the head office DB 2 'is in the update prohibited state, the update process 4' simply stops. And the unprocessed change request 3 remains, and the head office D
If B2 'is not in the update prohibited state, the next change request 3
Is processed.

The update process 4 'is in the idle state,
It is waiting for an event to be activated, and is activated when the head office DB 2 ′ is in an updatable state and a new change request 3 comes in.

The procedure of the unreflected ratio comparison process 28 will be described with reference to the flowchart of FIG.

The unreflected ratio comparison process 28 comprises only steps S11 and S13. In step S11, an excessive error is detected. That is, if the unreflected rate is higher than the reference (YES), the process proceeds to step S13 to immediately restore the quality, and immediately starts the duplication process 21 '(reflecting process).

The database system according to the present embodiment copies part or all of the original contents stored in one or more information storage devices and stores the copied contents in one or more other information storage devices. The rewriting performed on the original is intermittently reflected on the copy, and the timing of the reflection process is automatically controlled.

Further, the database system according to the present embodiment calculates or estimates the degree of error occurring between the information storage device groups due to intermittent reflection processing, and calculates the degree of error once obtained in the past. The above values are used as indices for controlling the timing.

Further, the database system according to the present embodiment calculates or estimates the ratio of the contents stored in a certain information storage device whose rewrite has not yet been reflected in another information storage device, and calculates the information. The above ratio is used as an index indicating an error generated between the storage device groups.

Further, the database system according to the present embodiment calculates or estimates the ratio of the content stored in a certain information storage device whose rewrite has not yet been reflected in another information storage device, and performs feedback. The above processing is performed for the processing to be performed.

Therefore, in the electronic telephone directory system according to the present embodiment, when the update process 4 ′ for updating the original DB (the head office DB 2 ′) stops processing after processing all unprocessed change requests 3, An unreflected ratio calculation process 27 and an unreflected ratio comparison process 28 are driven. Then, the comparison process 28 of the unreflected ratio drives the copy process 21 ′ to be reflected on the copy (branch DB 12 ′).

Further, the electronic telephone directory system determines whether or not to start the reflection process (replication process 21 ') based on the comparison result obtained by comparing the current unreflected ratio with the reference value. I do. Specifically, when the unreflected ratio exceeds the reference value, the duplication process 21 'is started and the head office DB 2'
Is reflected in the branch DB 12 '.

That is, in the electronic telephone directory system,
The load of calculating the unreflected rate is lower than the load of the reflection process,
By utilizing the fact that it can be almost ignored, the above-described direct and simple automatic control method of the reflection timing is realized.

[Embodiment 3] The following will describe still another embodiment of the present invention with reference to FIGS. 7 to 9. For convenience of explanation, members having the same functions as the members described in the first and second embodiments are given the same reference numerals, and descriptions thereof are omitted.

The present embodiment is an example in which the database system according to the present invention is applied to an electronic telephone directory system extending between branches. This embodiment corresponds to an application to the device described in the conventional example 4. Therefore, the entire configuration is the same as the device of the conventional example 4.

FIG. 9 is a DFD showing the entire configuration of the electronic telephone directory system according to the present embodiment. In addition, DFD
Is the same as that described in the above-mentioned conventional example 1.

The above electronic telephone directory system is a database system (equipment) for sharing electronic telephone directory data between the head office H and each branch Bn, Bs connected by a low-speed line. Here, since the electronic telephone directory system has a low line speed and is not suitable for interactive remote search, a copy of the head office DB 2 'is placed in each of the branches Bn and Bs. Then, in the normal search, the local store D
B2 ', 12 "... Only when the DB in the own premises is stopped due to a failure or a maintenance work.
Search for B.

Here, in the present embodiment, in order to maintain the consistency of the DB between the head office H and each branch Bn, Bs,
A method of giving the right to update the DB of each store by itself and adopting a method of appropriately synchronizing the contents of the DB of each store is adopted. That is, the DBs of the stores exchange information with each other, reflect the individually updated contents with each other, and match the contents of all the DBs. The electronic telephone directory system automatically controls the time interval for performing the synchronization process. In this embodiment, the branch DB1
2 ″ is different from the second embodiment in that it has an update function.

The outline of the synchronization process 21 ″ is as follows. First, updating of the DBs of all stores (main store DB 2 ′, branch DB 12 ″) is prohibited. Next, necessary information is collected from the update history of all stores. The necessary information is an update history of the update process that is processed after the start of the previous synchronization process 21 ″ and is not for the synchronization process 21 ″. Subsequently, based on the collected information, a group of insertion, update, and deletion operations necessary for the DBs of all stores are specified. Then, after reading the contents of the insertion and the update from the original DB, an update request is issued to the DB of each store. Finally, the update prohibition of the DB of all stores is released. For example, the record inserted in the north branch Bn is the branch DB1 of the north branch Bn.
2 "and inserted into the head office DB 2 'of the head office H and the branch DB 12" of the south branch Bs.

Here, the update request for the synchronous process 21 ″ is marked “for synchronous processing”. Then, when the update request is processed, the update history is also marked as “for synchronous processing”. The update history marked “for synchronization processing” is not subjected to synchronization processing. Note that the mark for “synchronous processing” attached to the update request is added to mark “for synchronous processing” on the update history that is a record of processing the update request.

Here, if the interval of the synchronization process 21 ″ is too short, update delay due to prohibition of DB update of all stores, load of equipment (apparatus and line) for collecting update history from all stores, and The electronic telephone directory system automatically controls the timing of the synchronization process 21 ″ to reduce the search quality while preventing the use of such waste, such as the load on the device for analyzing the update history. Can be kept.

Next, the function of the electronic telephone directory system will be described in detail with reference to the DFD shown in FIG.

The electronic telephone directory system comprises a head office terminal 1 ', a branch terminal 11, an actor, a head office DB (first information storage device) 2', a data store, an update request 3 ",
Update history 5, branch DB (second information storage device) 12 ″,
Update request 13, update history 15, last reflection time 22, reflection interval 23, unreflected ratio reference 26, and update processes 4 ″, update process 14, synchronization process (reflection means, reflection process) 21 ″, and time (Reflection control means, reflection control processing) 24, a reflection interval adjustment process (reflection interval setting means, reflection interval setting processing) 25, and a non-reflection rate calculation process 27 ''.

Each of the branches Bn and Bs includes the branch terminal 11, the branch DB 12 ″, the update request 13, and the update history 1
5 and an update process 14 are provided in pairs. Others are provided at the main store H.

First, each actor will be described.

The head office terminal 1 'is a terminal device for a user installed in the head office H. Head office terminal 1 'is head office DB
In addition to searching the electronic telephone directory DB 2 ', a request 3 "for updating the main store DB 2' is issued.
It is provided with a keyboard input device, a screen display device, and a printing device (printer).

The branch terminal 11 is a terminal device for a user installed in each of the branches Bn and Bs.
(Head office DB 2 'and branch DB 12 ") update request 13
Issue Although not shown, the branch terminal 11 can search the branch DB 12 ″, and can remotely search the head office DB 2 ′ while the branch DB 12 ′ is stopped.

Next, each data store will be described.

The head office DB 2 ′ is an electronic telephone directory DB installed in the head office H, and stores the electronic telephone directory DB. The main store DB 2 ′ is mainly searched from the main store H. Note that, unlike Embodiment 2, it is not positioned as an original. Although not shown, the head office DB 2 ′ may be remotely searched from the branch terminal 11 while the branch DB 12 ″ is stopped. Further, the head office DB 2 ′ and the branch DB 12 ″ store information whose contents are to be reflected. Device.

The update request 3 "is a request for updating the head office DB 2 '. The update request 3" is issued from the head office terminal 1' and is also issued from the synchronization process 21 "(described later).

The update history 5 is an accumulation of the history of the update processing performed by the update process 4 ″. The update history 5 is obtained by calculating the non-reflection rate in the non-reflection rate calculation process 27 ″.
The update history 5 is also used when the head office DB 2 'recovers from a failure.

The last reflection time 22 corresponds to the synchronization process 2
1 "(described later) is the last time the reflection was performed.
The last reflection time 22 is updated and stored each time the synchronization process 21 ″ is started.

The reflection interval 23 is determined by the synchronization process 21 ″.
Is the time interval at which the is to be performed, expressed in minutes. The reflection interval 23 is a reflection interval adjustment process 25.
It is updated and stored each time set by (described later).

The non-reflection rate reference 26 gives a reference value for adjusting the reflection interval (frequency) in the reflection interval adjustment process 25 (described later), that is, a reference value for activating the synchronization process 21 ″. The unreflected ratio reference 26 is input / changed (adjusted) by the user via the head office terminal 1 'and stored.

The above-mentioned branch DB 12 ″ stores each branch Bn, Bs
Is an electronic telephone directory DB installed in the Internet. Branch DB12 ″
Differs from the branch DB 12 'of the second embodiment in that it has an update function. Although not shown, the branch DB 12 ″
May be remotely searched from a terminal of another store while the DB of another store is stopped.

The change request 13 is a request for updating the branch DB 12 ″. The change request 13 is issued from the branch terminal 11 and also from the synchronization process 21 ″ (described later).

The update history 15 is an accumulation of the history of the update processing performed by the update process 14. Update history 15
Are used in the calculation of the non-reflection rate in the non-reflection rate calculation process 27 "and the synchronization process 21". In addition,
The update history 15 is also used when the failure of the branch DB 12 ″ is recovered.

Next, each process will be described.

The updating process 4 ″ updates the head office DB 2 ′ based on the updating request 3 ″. The update process 4 ″ is executed at any time based on the update request 3 ″.

The synchronization process 21 ″ synchronizes the contents between the store DBs. The synchronization process 21 ″ corresponds to the head office H
, And has a function of remotely controlling the facilities of each branch Bn and Bs via a line. Then, the electronic telephone directory system automatically adjusts the time interval for starting the synchronization process 21 ″.

The procedure of the synchronization process 21 "is as follows. First, the head office DB 2 'and each branch DB 12"
... is prohibited from being updated. Next, necessary information is collected from the update history 5 of the head office H and the update history 15 of each branch Bn, Bs. The necessary information is the history of the update processes 4 ″ and 14 that are processed after the start of the previous synchronization process 21 ″ and are not for the synchronization process 21 ″. A required insertion, update, and deletion operation group is specified for the DB 2 'and each branch DB 12 ". Then, after reading the contents of the insertion and the update from the original head office DB 2 'and each branch DB 12 "..., update requests 3" and 13 are issued to the head office DB 2' and each branch DB 12 ".... Head Office D
B2 'and the branch DBs 12 "...

The time comparison process 24 compares the time elapsed from the last reflection time 22 to the present with the reflection interval 23, and activates the synchronization process 21 ″ if the former is not smaller than the latter.

The reflection interval adjustment process 25 adjusts the reflection interval 23 by comparing the unreflected ratio with a reference value. The reflection interval adjustment process 25, which will be described later in detail with reference to FIG. 8, includes the following three internal processes. That is, the reflection interval adjustment process 25 includes an internal process for comparing the unreflected ratio with the reference value, an internal process for increasing the reflected interval 23 when the unreflected ratio is too small, and an internal process for increasing the reflected interval 23 when the unreflected ratio is excessive.
And reducing internal processing. Then, if the unreflected ratio is excessive, the synchronization process 21 ″ is immediately started.

The unreflected ratio calculation process 27 ″ periodically calculates an unreflected ratio indicating an error between the store DBs and feeds it back. Specifically, the unreflected ratio for the head office DB 2 ′ is calculated based on the unreflected ratio for each branch. Are obtained for the branch DBs 12 ″ of Bn and Bs, and the highest value among them is sent to the reflection interval adjustment process 25. In the electronic telephone directory system, the unreflected ratio between branches is not calculated.

The update process 14 updates the branch DB 12 ″ based on the update request 13. Here, the update process 14 is executed as needed based on the update request 13. That is, the update process 14 In the meantime, the DB search service is not stopped.
When 2 ″ is not being updated and is not in the update prohibited state, the change requests 13 are sequentially processed.
During the operation of the synchronization process 21 "and when the load is high, the update is prohibited. The suspension and activation of the update process 14 are the same as in the update process 4" of the head office H.

Here, the update process 4 ″ is executed as needed based on the update request 3 ″. In other words, the DB search service is not stopped due to the update process 4 ". The update process 4" sequentially processes the update requests 3 "when the head office DB 2 'is not being updated and is not in the update prohibited state. The head office DB 2 ′ is in an update prohibited state during the operation of the synchronization process 21 ″ and when the load is high.

Also, the update process 4 ″ is replaced with an update request 3 ″
At the time when one of the cases has been processed, it is determined whether or not to suspend. First, if there is no unprocessed update request 3 ″, or if the head office DB 2 ′ is in the update prohibited state, the process is suspended. Otherwise, 1 of the next update request 3 ″ is set.
Process the matter. In the second embodiment, the non-reflection rate calculation process 27 is started when the update process 4 ′ is suspended, but in the present embodiment, when the update process 4 ″ is paused, the non-reflection ratio calculation process 27 is performed. ″ Do not start.

The update process 4 ″ is executed in the idle state.
It is waiting for an event to be activated, and is activated when the head office DB 2 'is in an updated state and a new update request 3 "comes in.

The procedure of the reflection interval adjustment process 25 will be described with reference to the flowchart of FIG. In addition, FIG.
Steps S12 and S13 are added to the flowchart of FIG. 2 described in the first embodiment. This additional portion generates a control flow (error alarm) from the reflection interval adjustment process 25 to the synchronization process 21 ″ in FIG.

In step S12, the non-reflection rate is compared with the alert standard at that time, and it is determined that there is a risk that the non-reflection rate exceeds the reference (the non-reflection rate reference 26). If the unreflected ratio exceeds the alert standard, it is treated as if it exceeded the standard.

The above-mentioned alert criterion is obtained by calculating the coefficient calculated from the three values of the current time at the time of monitoring, the last reflection time 22, and the reflection interval 23 according to the following formula.
Calculate by multiplying by 6. Alert standard = unreflected rate standard 26 x (current time-last reflected time 22 + reflection interval 23) / (2 x reflection interval 23)

Here, at the moment when the reflection process is completed, the unreflected ratio has dropped to zero. Thereafter, as the update request is processed, the unreflected ratio increases. Therefore, during each time of the reflection process, the unreflection rate increases with time. Therefore, if the non-reflection rate is monitored, it is possible to predict the risk that the non-reflection rate exceeds the standard before the predetermined reflection interval elapses. Therefore, if the non-reflection rate exceeds the alert standard at the time of monitoring, it can be determined that there is a high risk that the non-reflection rate exceeds the standard before the predetermined reflection interval has elapsed.

In step S13, the unreflected rate is the reference (S
11) Or because it exceeds the alert standard (S12),
Immediately, an error warning is issued to start the synchronization process 21 ″ (reflection processing). Then, the process proceeds to step S16 ′ to reduce the reflection interval 23. Specifically, the unreflection rate (error) is changed to the reflection interval 23. Is adjusted in proportion to the non-reflection rate and its reference.In other words, if the non-reflection rate is F times the reference, the reflection interval 23 is set to 1 / F. T in the following is given by the following equation: T = min (reflection interval 23, last reflection time 22-current time)

Steps S12, S13, S16 '
The other steps are the same as those in FIG. Further, the arithmetic expression in each step in the flowchart is an example, and the present invention is not limited to this.

Here, the present embodiment is based on the premise that the update request arrives at a certain time at a constant pace. If the update request arrives at a completely constant pace, the alert criterion can be determined by the following simplified formula: Warning standard = standard of non-reflection rate 26 x (current time-last reflection time 22) / reflection interval 23

However, the actual update request arrives at random, and the alert criterion is used to make a prediction in consideration of this point. Therefore, it is necessary to consider the number of samples used for prediction. The shorter the time from the previous reflection process to the present, the smaller the number of samples.
Then, in this situation, when the alert criterion is obtained by the above-described simplified formula, the risk of an error alarm being a false alarm increases. In addition, the shorter the time from the previous reflection process to the present, the more margin should be given to the criterion, and the caution criterion can be relaxed. Thereby, false information can be avoided. The formula of the alert criterion in step S12 is determined based on this concept.

Further, in the first embodiment, the reflection process (indexing process 21) is a process for calculating the unreflected ratio.
7 were independent of the rewriting of the original (document file group 2). In the second embodiment, the update of the head office DB 2 ′ (original) drives an unreflected ratio calculation process 27 and an unreflected ratio comparison process 28. Then, the non-reflection rate comparison process 28 drives the reflection process (copy process 21 ').

On the other hand, in the present embodiment, there are two possible timings for activating the unreflected ratio calculation process 27 ″, both of which are independent of the update of the DB. Reflection processing (synchronization process 2)
1 "). The other is a predetermined time interval (hereinafter," monitoring interval ") by the time comparison process 24.
It is written. ). In the present embodiment, the non-reflection rate calculation process 27 ″ is started at an interval of one eighth of the reflection interval 23.

The monitoring interval is an arbitrary time interval shorter than the reflection interval 23. According to the experiment, the longer the monitoring interval is, the more defects (phenomenon that the unreflection ratio exceeds the standard) occur more frequently. However, even if the monitoring interval is set to be less than 1/8 of the reflection interval, the effect of reducing the defects is not improved. Did not. Therefore, in the present embodiment, the monitoring interval is set to ８ of the reflection interval based on the experimental results.

In the present embodiment, the reflection interval 23 is automatically adjusted, but the monitoring interval can be automatically adjusted. In other words, the monitoring interval can be controlled by the defect occurrence rate in the same manner as the reflection interval 23 is controlled by the unreflected rate.

In each of the embodiments, the automatic control method of the reflection time is to compare the current non-reflection rate with the reference value, but the way of handling the comparison result is different. The first embodiment is an indirect method in which the reflection interval is adjusted according to the comparison result. In the second embodiment, it is a direct method of determining whether to start the reflection process based on the comparison result. In the present embodiment, both are used together.

In the database system according to the present embodiment, the contents of some or all of the information storage devices are kept the same, and the rewriting of some of the information storage devices is intermittently performed by other information storage devices. And automatically controls the timing of the reflection process.

Further, the database system according to the present embodiment calculates or estimates the degree of error occurring between the information storage device groups due to intermittent reflection processing, and calculates the error once obtained in the past. The above values are used as indices for controlling the timing.

Further, the database system according to the present embodiment calculates or estimates the ratio of the contents stored in a certain information storage device whose rewrite has not yet been reflected in another information storage device, and calculates the information storage device. The above ratio is used as an index indicating an error generated between the groups.

In addition, the database system according to the present embodiment calculates or estimates the ratio of contents whose rewrite has not yet been reflected in another information storage device among contents stored in a certain information storage device, and feeds it back. The above processing is performed.

As described above, in the database system according to the present invention, the timing of the synchronization processing (reflection processing) is not controlled manually by the user or simply at fixed time intervals, but is dynamically controlled according to the situation. This makes it possible to optimally maintain the balance between the two conflicting factors of information identity and device load.

That is, in the control method of the database system according to the present invention, the timing of the reflection process between the information storage devices is not manually operated by the user or a simple fixed time interval, but is dynamically changed according to the situation. Control. In particular,
The control method of the database system adjusts the time interval of reflection according to a predetermined condition or calculation, or
Start to reflect when the specified conditions are met, or
When the predetermined condition is not satisfied, the timing of the reflection process is automatically controlled so that the reflection is not started. Accordingly, the balance between the two conflicting factors of information accuracy and device load can be optimally maintained.

Further, in the control method of the database system according to the present invention, the timing of reflection is controlled according to the degree of error occurring between the information storage device groups. for that reason,
The database system calculates or estimates how much error will occur when the result is compared with the result of reading or searching, the result of current execution, the result of rewriting, and the result of rewriting. At this time, the degree of error is determined by a method with a lighter load than actually executed and compared or actually executed. Then, the timing of reflection is controlled based on the calculated value or the estimated value.

As a specific method of controlling the reflection time, for example, a method of adjusting the reflection time interval so that the index error falls within a predetermined range, or a method of reflecting when the error exceeds a predetermined reference. And a method in which reflection is not started when the error falls within a predetermined standard.

The control method of the database system according to the present invention includes a method of calculating or estimating a ratio of contents whose rewrite has not yet been reflected in another information storage device among contents stored in one information storage device. You may go out. Then, this ratio can be used as an index representing the “degree of error generated between the information storage device groups”.

Thus, in the database system, in a plurality of information storage device groups, rewriting performed on a certain information storage device is repeatedly reflected on other information storage devices.
The timing at which the reflection process is executed can be automatically controlled.

In the database system according to the present invention, in a plurality of information storage device groups, means for repeatedly rewriting rewriting performed on a certain information storage device to another, and timing for executing reflection processing using the means are automatically set. Control means. Alternatively, the database system includes means for automatically controlling the timing of the reflection process.
Alternatively, the database system includes means for calculating or estimating a degree of an error generated between the information storage devices due to intermittent reflection processing, and means for feeding back the error for automatic control. . Alternatively, the database system calculates or estimates a ratio of contents stored in a certain information storage device whose rewrite has not yet been reflected in another information storage device, and feeds it back for automatic control. Means. Note that these means execute the corresponding control method described above.

A recording medium on which the control method of the database system according to the present invention is recorded stores a program for executing the above method in a computer-executable manner.
Then, by reading this program, the storage can be reproduced, and the reproduced program can be executed by one or more information processing devices. By executing in this way, the object of the present invention can be achieved.

Further, the recording medium stores a program for executing a method for automatically controlling the timing of reflection in the database system. Then, by reading this program, the storage can be reproduced, and the reproduced program can be executed by one or more information processing devices in combination with the means described below. The means is realized by executing means (including a program) specific to the device or a program read from some medium,
The object of the present invention can be achieved by executing both means in combination.

Further, the recording medium stores a program for executing a method of calculating or estimating a degree of an error occurring between information storage apparatuses due to intermittent reflection processing in the database system and feeding back the information. are doing. Then, by reading this program, the storage can be reproduced, and the reproduced program can be executed by one or more information processing devices in combination with the means described below. The means is realized by executing a means (including a program) specific to the device or a program read from some medium. By executing the two means in combination, the object of the present invention is achieved. Can be achieved.

Further, in the above-mentioned recording medium, a method of calculating or estimating a ratio of contents whose rewriting has not yet been reflected on another information storage device, and feeding back the content, in a database system, among contents stored in one information storage device. Is stored. Then, by reading this program, the storage can be reproduced, and the reproduced program can be executed by one or more information processing devices in combination with the means described below. The means is realized by executing a means (including a program) specific to the device or a program read from some medium. By executing the two means in combination, the object of the present invention is achieved. Can be achieved.

The present embodiment does not limit the scope of the present invention, and various changes can be made within the scope of the present invention. For example, the present invention can be configured as follows.

The method for controlling a database system according to the present invention is a method for intermittently reflecting rewriting performed on a part of information storage devices in another in a plurality of information storage devices. May be automatically controlled.

Accordingly, the database system dynamically controls the timing of the reflection processing between the information storage devices according to the situation without manually operating the user or simply at a fixed time interval. The balance between the two conflicting factors of accuracy and equipment load can be optimally maintained.

In the control method of the database system according to the present invention, in order to facilitate search for one or more information storage devices, information for search assistance is generated and another one or more information storage devices are stored. A method of storing in a device, a method of intermittently reflecting rewriting performed on a search target information storage device in information for search assistance, and a method of automatically controlling the timing of reflection processing. .

Thus, the database system can set the time of the reflection process from the search target to the search auxiliary information.
Without manual operation of the user or simple fixed time intervals,
By dynamically controlling according to the situation, it is possible to optimally maintain a balance between two conflicting factors, that is, search quality and device load.

According to the control method of the database system according to the present invention, a part or all of the original contents stored in one or more information storage devices is copied and stored in one or more other information storage devices. This is a method of intermittently reflecting the rewrite performed on the original to the copy, or a method of automatically controlling the timing of the copy processing (reflection processing).

Thus, the database system dynamically controls the timing of the duplication process (reflection process) according to the situation without manually operating the user or at a simple fixed time interval. The balance between the two opposing factors, namely, performance and equipment load, can be optimally maintained.

The method for controlling a database system according to the present invention is a method for keeping a part or all of the contents the same among a plurality of information storage devices, and rewriting some of the information storage devices. It may be a method of intermittently reflecting on another, or a method of automatically controlling the timing of the synchronization processing (reflection processing).

Thus, the database system dynamically controls the timing of the synchronization processing (reflection processing) according to the situation instead of manually operating the user or at a simple fixed time interval, so that the same information can be obtained. The balance between the two opposing factors, namely, performance and equipment load, can be optimally maintained.

According to the control method of the database system of the present invention, the degree of error occurring between the information storage device groups due to the intermittent reflection processing is obtained by calculation or estimation, and the past error is calculated. A method using one or more values as an index for controlling the timing may be used.

Thus, the database system uses the degree of error generated between the information storage means groups due to intermittent reflection processing as an index for controlling the timing of the reflection processing, thereby obtaining the information. The accuracy can be appropriately evaluated and the balance with the load on the device can be maintained optimally.

The method for controlling a database system according to the present invention calculates and estimates the ratio of the contents stored in a certain information storage device whose rewrite has not yet been reflected in another information storage device. A method using the above ratio may be used as an index indicating an error generated between the storage device groups.

Thus, the database system uses the non-reflection rate as an index for controlling the timing of the reflection processing, and thereby the degree of error occurring between the information storage device groups due to intermittent reflection processing. Can be appropriately evaluated at a relatively low cost.

The recording medium storing the control method of the database system according to the present invention may store a program for executing the control method. Thereby, not only the form in which the control method is built in one specific information processing apparatus but also the form of an independent recording medium in which a program for executing the control method is separated from the specific one information processing apparatus By doing so, it becomes possible to store, transport, distribute, and distribute.

That is, the recording medium may store a program for executing the above-described automatic control method for automatic control of the timing of the reflection process. Then, the database system may realize the automatic control method by executing a program of the automatic control method stored in the recording medium.

According to the recording medium, the automatic control method is executed not only in a form built in a specific one information processing apparatus but also in the specific one information processing apparatus. By separating the program into a form of an independent recording medium, storage, transportation, distribution, sale, and the like can be performed. In addition, the automatic control method is not limited to a part of the reflection method, but is also separated from a specific reflection method by a program for executing the automatic control method, and is stored, transported, and distributed in an independent recording medium. , Sales, etc. become possible. In addition, it is possible to design, manufacture, and the like in which a device that performs the automatic control method is separated from a specific reflection method.
Also, by separating, a plurality of reflection methods and a plurality of automatic control methods can be arbitrarily combined.

Similarly, in the recording medium, the method of calculating or estimating and feeding back the degree of an error that occurs between the information storage devices due to intermittent reflection processing is used in the above-described error handling method. May be stored. The database system may implement the error handling method by executing a program of the error handling method stored in the recording medium. The effect of the recording medium is obtained by reading the automatic control method as an error handling method in accordance with the automatic control method.

[0209] Similarly, the recording medium calculates or estimates the ratio of contents whose rewrite has not yet been reflected in another information storage device among the contents stored in a certain information storage device, and performs processing for feeding back. A program for executing the method of handling the unreflected ratio may be stored. Then, the database system may realize the method of handling the unreflected rate by executing a program of the method of handling the unreflected rate stored in the recording medium. The effect of the recording medium is obtained by reading the automatic control method as a method of handling the non-reflection ratio according to the automatic control method.

Lastly, the database system described in each of the above embodiments includes a plurality of devices (for example, a host computer, a terminal computer, an interface device,
Even when applied to a system composed of network devices, printers, etc., a device composed of one device (for example,
Portable computer, word processing device, etc.).

[0211] Further, an object of the present invention is to provide a system or apparatus with a recording medium in which program codes (executable program, intermediate code program, source program), which are software for realizing the above-described functions, are recorded in a computer-readable manner. It can also be achieved by supplying the program and the computer (or CPU or MPU) of the system or the apparatus reads out and executes the program code recorded on the recording medium. In this case, the program code itself read from the recording medium realizes the above-described function, and the recording medium on which the program code is recorded constitutes the present invention.

The recording medium for supplying the program code can be configured to be separable from the system or the device. Further, the recording medium may be a medium that fixedly carries the program code so that the program code can be supplied. Even if the recording medium is mounted on a system or an apparatus so that a computer can directly read the recorded program code, the recording medium may be connected to a system or apparatus as an external storage device via a program reading apparatus connected to the system or the apparatus. It may be mounted so that it can be read.

For example, the recording medium may be a tape system such as a magnetic tape or a cassette tape, a magnetic disk such as a floppy (registered trademark) disk / hard disk, or a CD.
A disk system including an optical disk such as ROM / MO / MD / DVD / CD-R, a card system such as an IC card (including a memory card) / optical card, or a mask ROM /
A semiconductor memory system such as an EPROM / EEPROM / flash ROM can be used.

Further, the program code may be recorded so that the computer can read out from the recording medium and directly execute the program code, or the program code is transferred from the recording medium to the program storage area of the main storage and read out from the main storage by the computer. It may be recorded so that it can be executed.

Further, the recording medium may be a medium that carries the program code in a fluid manner so that the program code can be supplied via a communication network or the like. In this case, the system or device can be configured to be connectable to a communication network (including the Internet or the like), and the program code can be supplied by downloading from the communication network.

A program for reading a program code from a recording medium and storing the program code in a main memory;
It is assumed that the program for downloading the program code from the communication network is stored in a system or an apparatus in advance so as to be executable by a computer.

The functions described above are realized not only by the computer executing the above-described program code read out, but also by the OS or the like running on the computer performing one of the actual processing based on the instruction of the program code. It is also realized by performing part or all.

[0218] Further, the above-mentioned function is realized after the above-mentioned program code read from the above-mentioned recording medium is written into a memory provided in a function expansion board mounted on a computer or a function expansion unit connected to the computer. Based on the instructions of the program code, the functions are also realized by the CPU or the like provided in the function expansion board or function expansion unit performing part or all of the actual processing.

[0219]

As described above, the database system of the present invention intermittently changes the first information storage device, the second information storage device, and the changes made to the first information storage device. Reflecting means for reflecting on the second information storage device, and reflection control for controlling activation of the reflecting means in accordance with the degree of error between the contents of the first information storage device and the contents of the second information storage device. Means.

Further, as described above, the control method of the database system according to the present invention is a control method of the database system having the first information storage device and the second information storage device, wherein A reflection process for intermittently reflecting a change made to the storage device to the second information storage device, and a difference between the content of the first information storage device and the content of the second information storage device. And a reflection control process for controlling activation of the reflection process.

Further, the computer-readable recording medium of the present invention has recorded thereon a control program for controlling a database system having a first information storage device and a second information storage device as described above. A computer-readable recording medium for intermittently reflecting a change made to a first information storage device to a second information storage device; Second
And a program for causing a computer to execute a reflection control process for controlling activation of the reflection process in accordance with the degree of error with the content of the information storage device.

Therefore, in the above-mentioned database system, the reflection control process performs the reflection process according to the degree of error (unreflection rate) between the content of the first information storage device and the content of the second information storage device. Startup is controlled.

Therefore, in the above database system,
The load of calculating the unreflected rate is lower than the load of the reflection process,
When almost negligible, the start of the reflection process can be directly and simply automatically controlled.

Therefore, in a database system in which the contents are made the same while allowing a certain error among a plurality of information storage devices (databases and the like), the timing of the reflection process is determined by a manual operation of the user or a simple operation. By performing dynamic control according to the situation instead of at regular time intervals, an effect is obtained that the balance between two contradictory elements, ie, the identity of information and the load on the device, can be optimally maintained.

As described above, in the database system of the present invention, the reflection control means may further control the reflection based on the degree of error between the contents of the first information storage device and the contents of the second information storage device. This is a configuration including a reflection interval setting unit that sets a reflection interval for intermittently starting the reflection unit.

As described above, in the control method of the database system according to the present invention, the reflection control process may further include the step of determining the degree of error between the content of the first information storage device and the content of the second information storage device. And a reflection interval setting process for setting a reflection interval for intermittently starting the reflection process based on the above.

Further, as described above, the computer-readable recording medium of the present invention further comprises the program, wherein the reflection control processing is performed so that the content of the first information storage device and the content of the second information storage device are different. Based on the degree of error with
This configuration includes a reflection interval setting process for setting a reflection interval for intermittently starting the reflection process.

Therefore, in the above-mentioned database system, the reflection interval setting process allows the content of the first information storage device and the content of the second information storage device to be determined in accordance with the degree of error (unreflection rate). By setting the reflection interval, it is possible to control so that the reflection process is started at each reflection interval.

Thus, in the above database system,
When the load for calculating the non-reflection rate cannot be ignored compared to the load for the reflection processing, the reflection timing can be automatically controlled by an indirect method of adjusting the reflection interval.

Therefore, in a database system in which the contents are made the same while allowing a certain error between a plurality of information storage devices (databases and the like), the timing of the reflection processing is set by the user's manual operation or simple operation. Dynamic control according to the situation instead of fixed time intervals prevents conflicting overload of equipment due to excessive frequency and decrease of information accuracy due to underfrequency, while maintaining the sameness of information and load of equipment This has the effect that the balance between the two factors can be optimally maintained.

[Brief description of the drawings]

FIG. 1 is a data flow diagram schematically showing functions of a document editing apparatus to which a database system according to an embodiment of the present invention is applied.

FIG. 2 is a flowchart showing a procedure of a reflection interval adjustment process of the document editing apparatus shown in FIG. 1;

FIG. 3 is a data flow diagram schematically showing functions of an electronic telephone directory system to which a database system according to another embodiment of the present invention is applied.

FIG. 4 is a flowchart showing a procedure of a comparison process of a non-reflection ratio of the electronic telephone directory system shown in FIG. 3;

FIG. 5 is a data flow diagram showing an outline of functions of the electronic telephone directory system shown in FIG. 3 at normal times in the entire configuration.

6 is a data flow diagram showing an outline of functions at the time of failure or maintenance work of the entire configuration of the electronic telephone directory system shown in FIG. 3;

FIG. 7 is a data flow diagram schematically showing functions of an electronic telephone directory system to which a database system according to still another embodiment of the present invention is applied.

8 is a flowchart showing a procedure of a reflection interval adjusting process of the electronic telephone directory system shown in FIG. 7;

9 is a data flow diagram schematically showing functions of the entire configuration of the electronic telephone directory system shown in FIG.

FIG. 10 is a data flow diagram schematically showing functions of a document editing apparatus according to a conventional example of the present invention.

FIG. 11 is a data flow diagram schematically showing functions of a supplier database system according to another conventional example of the present invention.

12 is a data flow diagram schematically showing functions of the overall configuration of the supplier database system shown in FIG.

FIG. 13 is a data flow diagram showing an outline of functions in a normal state of an electronic telephone directory system according to still another conventional example of the present invention.

FIG. 14 is a data flow diagram schematically showing functions of the entire configuration of the electronic telephone directory system shown in FIGS. 13 and 15 at the time of failure or maintenance work.

FIG. 15 is a data flow diagram showing an outline of functions in a normal state of an electronic telephone directory system according to still another conventional example of the present invention.

[Explanation of symbols]

2 Document file group (first information storage device) 2 'Head office DB (first information storage device) 12 Index (second information storage device) 12' Branch DB (copy) (second information storage device) 12 "Branch DB (second information storage device) 21 Indexing process (reflecting means, reflecting process) 21" Duplicating process (reflecting means, reflecting process) 21 "Synchronous process (reflecting means, reflecting process) 23 Reflection interval 24 hours Comparison process (reflection control means, reflection control processing) 25 Reflection interval adjustment process (reflection interval setting means,
Reflection interval setting process) 28 Comparison process of non-reflection rate (reflection control means, reflection control process)

Claims (6)

[Claims] A first information storage device, a second information storage device, and a reflection unit for intermittently reflecting a change made to the first information storage device to the second information storage device. And a reflection control means for controlling activation of the reflection means in accordance with the degree of error between the content of the first information storage device and the content of the second information storage device. system. 2. The reflection control means sets a reflection interval for intermittently activating the reflection means based on a degree of an error between the content of the first information storage device and the content of the second information storage device. 2. The database system according to claim 1, further comprising: a reflection interval setting unit for performing the setting. 3. A method for controlling a database system comprising a first information storage device and a second information storage device, wherein a change made to the first information storage device is intermittently transmitted to the first information storage device. A reflection process for reflecting the information on the second information storage device; a reflection control process for controlling activation of the reflection process according to the degree of error between the content of the first information storage device and the content of the second information storage device. A method for controlling a database system, comprising: 4. The reflection control process sets a reflection interval for intermittently starting the reflection process based on the degree of error between the contents of the first information storage device and the contents of the second information storage device. 4. The control method for a database system according to claim 3, further comprising a reflection interval setting process. 5. A computer-readable recording medium on which a control program for controlling a database system having a first information storage device and a second information storage device is recorded, wherein the first information storage device is provided. A reflection process for intermittently reflecting the change made to the second information storage device with the second information storage device, and according to the degree of error between the content of the first information storage device and the content of the second information storage device. And a computer-readable recording medium storing a program for causing a computer to execute a reflection control process for controlling activation of the reflection process. 6. The computer-readable storage medium according to claim 6, wherein the reflection control processing is performed so that the content of the first information storage
6. The computer-readable storage medium according to claim 5, further comprising a reflection interval setting process for setting a reflection interval for intermittently starting the reflection process based on a degree of an error with the content of the information storage device. Possible recording medium.