JP2524450B2 - Search system - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a search system for simultaneously searching a database using a plurality of computers in parallel.

[0002]

2. Description of the Related Art In recent years, databases that store various data in various fields have been developed, and these databases can be searched by a search system using a computer. By accessing these databases using a search system, it is possible to accurately obtain the necessary data from a vast amount of data in a short time.

[0003]

However, when accessing a huge database, there is a problem that the search time for obtaining necessary data becomes long.
In addition, the number of users of the search system is increasing with the general use of databases, and it is desired to reduce the time required for the search. Further, when the database is accessed via a communication line such as a telephone line, data transmission is serially performed, and the data transmission speed is slow, so that the time required for the search becomes longer.

The present invention solves such conventional problems, and an object of the present invention is to provide a search system which can access a database in a short time.

[0005]

A search system according to the present invention is a search system for searching a search target composed of at least one database, and a condition setting computer for setting a search condition for the search target, Search condition storage means for storing search conditions, and a plurality of search areas each of which is obtained by dividing the search target into a predetermined size are provided in correspondence with each search area, and each search area is in a non-search state, a search state, and a search completion state. And a plurality of computers that operate independently of each other and perform a search of any one of the search areas according to the search conditions stored in the search condition storage means. And a search result storage unit that stores a search result obtained in each of the computers, wherein each computer sets a flag in an unsearched state. The search area corresponding to the flag is searched, the obtained search result is output to the search result storage means, and the search cycle for setting the search state flag to the search completed state is executed. ,
It is characterized in that the search cycle is repeated until all of the unsearched flags are in the search completed state.

If there is a flag among the flags that is not set to the search completion state even after a predetermined time has elapsed after being set to the search state, the search cycle of the search area corresponding to the flag is changed. A configuration executed by a computer other than the computer executing the search cycle of the search area can be added.

Further, each of the computers may be configured to search for the search target via a communication line.

[0008]

In the search system having the above-described structure, it is possible to search for a search target composed of one or more databases. The search target is divided into a plurality of search areas having a predetermined size, and each search area is provided with a flag indicating whether it is in the unsearched state, the search state, or the search completed state. , These flags are held in the flag storage means.

In the search system of the present invention, the search conditions are first set in the search condition storage means. When the search condition is set, each computer sequentially starts executing the following search cycle. That is, the search cycle includes a step of detecting whether there is an unsearched flag in the flag storage means,
When there is a flag in the unsearched state, the computer sets the flag to the search state, executes the search in the search area corresponding to the flag, and stores the search result obtained after the search is completed in the search result storage. And a step of setting the flag in the flag storage means to the search completion state. Each computer is
Such a search cycle is sequentially executed for the search area in which the flag has not been searched. Then, the computer that has completed the search again accesses the flag storage means, and if there is a flag in the unsearched state, further executes the search cycle for the search area corresponding to the flag. Since each computer operates independently of the others, the computer that searches the search area with less search data moves to the next search cycle earlier, and the computer that searches the search area with more search data moves to the next search cycle. It will take a long time to transfer. Then, the search cycle is repeatedly executed until all the flags are in the search completed state.

When all the flags are in the search completed state, the search for the search target is terminated.

As described above, in the search system of the present invention,
By using multiple computers that operate independently, it is possible to perform searches in parallel at the same time. Further, in the search system of the present invention, by providing the flag storage means, each computer can execute the search in the search area without being influenced by other computers and without overlapping each other. In the above search system, when one of the plurality of computers cannot continue the search due to a hardware failure or the like, the flag of the flag storage means remains set to the search state, and the search system completes the search. Can not do it.

In preparation for such a case, the system of the present invention measures the time after the flag is set to the search state, and when this time is larger than a preset value, another computer is used. The search area is searched. As a result, even if any of the computers becomes defective, the search can be completed normally.

If the search target is in a remote location,
Each computer can search for a search target via a communication line such as a telephone line. Further, even when the search target is composed of databases existing in a plurality of different places, each computer can perform a search by connecting a telephone line to each database having a search area to be searched.

[0014]

Embodiments of the present invention will be described below in detail with reference to the drawings. In this embodiment, a system for accessing a database containing company data nationwide through a public telephone line and searching for a company with a specific name will be given.

The structure of the search system of this embodiment is schematically shown in FIG. The search system according to the present embodiment includes eleven personal computers 1, 1 ... Which can operate independently of each other, and each personal computer 1, 1 ... 1 through each interface board (IF board) 2, 2. Is connected to one disk sharing device 14. A condition setting / maintenance system 16 and a data processing / printing system 20 are connected to the disk sharing device 14. Further, one shared hard disk 15 is connected to the disk sharing device 14. Therefore, the shared hard disk 15 includes 11 personal computers 1,
1, and the condition setting / maintenance system 16 and the data processing / printing system 20. As shown in FIG. 2, the shared hard disk 15 is provided with a search monitor area 25, a print / edit monitor area 26, and a work area 27.

The condition setting / maintenance system 16 includes a personal computer 18 which is a condition setting computer.
And a CRT 19 and a flexible disk drive 17 for data storage. Further, the data processing / printing system 20 includes a processing hard disk 21.
And a personal computer 22, a CRT 24, and a printer 23. The disk sharing device 14 is composed of 11 personal computers 1,
1 ..., the personal computer 18, and the personal computer 22 have a function of adjusting a conflict when the shared hard disk 15 is simultaneously accessed.

Each personal computer 1, 1 ... Has a modem 12, 12, ... And can be connected to the database 32 via the public telephone line 3.
The database 32 includes a host computer 30 and a data file 31, and the host computer 30 is connected to a plurality of computers by time sharing and searches the data file 31. Therefore, each personal computer 1, 1 ... Can be simultaneously connected to the host computer 30 of the database 32,
At the same time, the database 31 can be searched. In the present embodiment, the database 31 is recorded with company data as described above.

In the search system of this embodiment, the personal computer 1, 1, ... Is accessed for each search area obtained by dividing the database 31 into units such as prefectures, counties, cities, towns, villages and the like. Data such as a telephone number for connecting to the host computer 30 and what kind of search area the database 31 is divided into is stored in the search condition file in advance by the personal computer 18 of the condition setting / maintenance system 16. Alternatively, it is stored in each personal computer 1, 1.

The operation of the search system of this embodiment will be described with reference to the flowchart shown in FIG. First, set the conditions
The personal computer 18 of the maintenance system 16 is
Set search conditions, print conditions for search results, etc. The search condition includes a company name to be searched, a search area, and the like.
These search conditions are newly created or created by changing, adding or canceling the contents of the search condition file already stored in the search monitoring area 25. As shown in step 41 of FIG. 3, the created search condition is the search condition storage area 28 of the search monitoring area 25.
(FIG. 2). The search conditions can be created and stored even while the search by the personal computers 1, 1 ... Described below is being performed.

Each of the personal computers 1, 1 ... Monitors the search condition storage area 28 of the search area 25 for search in sequence. When it is detected that the search condition is set in the search condition storage area 28, it is detected. Then, the personal computer 1 creates the access flag file 29 in the search monitoring area 25 and sets all the flags in the access flag file 29 to "1" (step 42). The flag "1" represents the unsearched state. Each flag in the access flag file 29 is provided corresponding to each search area. Therefore, the number of search areas and the number of flags are the same. In this embodiment, the search condition storage area 28 functions as a search condition storage means, and the access flag file 2
9 functions as a flag storage means.

Next, each personal computer 1, 1 ...
Determines whether the access flag file 29 has a flag with a value of "1", as shown in step 43 of FIG. If there is a flag with a value of "1", as shown in step 44 of FIG.
One flag having a value of "1" is set to "2". Next, the database 32 is accessed via the public telephone line 3 (FIG. 1), and the search area corresponding to the flag is set as the search monitoring area 25. The search is performed according to the search condition set in the search condition storage area 28 (step 45), where the flag "2" indicates the search state.

As described above, each of the personal computers 1, 1 ... Sequentially stores “1” in the access flag file 29.
Flag is set to "2" and the search area corresponding to the flag is performed. Then, each personal computer 1 that has completed the search outputs the search result to the work area 27 of the shared hard disk 15, as shown in step 46 of FIG. In this embodiment, the work area functions as a search result storage means. The personal computer 1 that has output the search result sets the flag of the search area for which the search has been completed to "3", as shown in step 47 of FIG. Here, the flag "3" indicates the search completion state. Such steps 43 to 47 correspond to one search cycle.

Next, the personal computer 1 that has completed the search cycle determines whether or not there is a flag having the value "1" in the access flag file 29, as shown in step 43. If there is a flag having a value of "1", the flag is set to "2", and the search area corresponding to the flag is searched according to the search condition set in the search monitoring area 25 as in the above (step 45). ). As described above, each personal computer 1, 1 ... Independently searches the search area independently, and the personal computer 1 that completes the search cycle in a short time starts the next search cycle early and the search cycle takes a long time. The personal computer 1 that has required a long time will take a long time before shifting to the next search cycle.

In this way, when the unsearched search area, that is, the flag having the value of "1" disappears, each personal computer 1, 1 ... Ends the search of the search area. Then, as shown in step 48 of FIG. 3, it is determined whether or not all the flags are set to "3", and if all the flags are set to "3", that is, all the search areas are searched. If the search for is completed, step 49 in FIG.
Finally, the personal computer 1 having the flag set to “3” transfers all the search data stored in the work area 27 to the print / edit monitoring area 26 of the shared hard disk 15.

When the transfer of all search data is completed, each personal computer 1, 1 ...
The monitoring of the search condition storage area 28 of No. 5 is started. Personal computer 1 for the condition setting / maintenance system 16
If the search condition is set in the search condition storage area 28 by 8, each personal computer 1, 1 ... Starts the search again, and if not set, the monitoring of the search condition storage area 28 is continued. .

On the other hand, the personal computer 22 of the data processing / printing system 20 constantly monitors the printing / editing monitoring area 26, and all search data in the work area 27 is transferred to the printing / editing monitoring area 26. Then, the search data is printed according to the print condition data stored in the search monitoring area 25 (step 50).

When the printing is completed, the monitoring of the printing / editing monitoring area 26 is continued again. As described above, the data processing / printing system 20 includes each personal computer 1,
1, ... Independent of the condition setting / maintenance system 16 and the like, and starts printing only when data is transferred to the printing / editing monitoring area 26.

Further, the personal computer 18 of the condition setting / maintenance system 16 stores the search result of the print / edit monitoring area 26 in the flexible disk via the flexible disk drive 17, as shown in step 51 of FIG. And ends the search.

In the search system of this embodiment, if any one of the personal computers 1 fails, it can be restored. That is, after the personal computer 1 changes the value of the flag from "1" to "2" as described above, if a failure occurs during the search in the search area and the search cannot be completed, another personal computer 1 The search in that search area is performed on behalf of the user. Whether or not to perform the search by the alternative personal computer 1 is determined by determining whether the required search time is longer than a predetermined set time, as shown in step 52 of FIG.

When it is detected in step 52 that the required search time is longer than the set time, the search area is searched by another personal computer 1 and the search result is output as shown in step 53 (step 54). ),
The flag of the search area is set to "3" (step 5)
5). After that, the process returns to step 48 and all the flags are "
3 "is confirmed, the above steps 49 to 49 are performed.
51 continues.

The above measurement of the required search time may be started immediately after changing the value of the flag, or may be started after all the flags other than that flag are set to "3".

Further, the set time can be appropriately determined according to the size of the search area and the like. As described above, in the present embodiment, since the plurality of personal computers 1, 1 ... Are used so that they can operate independently, the failure recovery function can be easily realized.

In this embodiment, the case where the search target is composed of only one database has been described, but the present invention can be applied to the case where the search target is composed of two or more databases, and each database exists in a different place. It can also be applied to the case. In this case,
The telephone number for each database is stored in the search condition file or stored in each personal computer 1, 1.

Further, in the present embodiment, the personal computers 1, 1 ... Which conduct the search all have the same specifications.
It is possible to use those having different specifications, and it is also possible to use personal computers having different processing speeds.

Further, in the present embodiment, when the flag of the value "1" disappears, the personal computer 1 which has completed the search of the search area waits until the search of all the search areas for the search target is completed. The personal computer 1 that has completed the search may start a search for the next search target search area. With such a system, the time required for the search can be further shortened.

[0036]

In the search system according to the present invention, a plurality of search areas can be searched at the same time by a plurality of independently operating computers, so that the time required for the search can be greatly reduced. Therefore, many users can use the search system with a short waiting time. Further, even when the database is accessed via a telephone line or the like in which data is transmitted serially, the search can be performed in a short time.

Further, in the search system according to the present invention, when a failure occurs in one of the searching computers,
Since the other computer performs the search on behalf of the faulty computer, the fault recovery function can be easily provided. Therefore, according to the present invention, a very reliable search system can be obtained.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of an embodiment of a search system of the present invention.

FIG. 2 is a conceptual diagram showing a storage area of a shared hard disk in the search system of FIG.

3 is a flowchart showing a search process in the search system of FIG.

[Explanation of symbols]

 1 ... Personal computer 2 ... Interface board 3 ... Public telephone line 12 ... Modem 14 ... Disk sharing device 15 ... Shared hard disk 16 ... Condition setting / maintenance system 17 ... Data storage flexible disk drive 18 ... Personal computer 22 ... Personal computer 23 ... Printer 25 ... Search Monitoring Area 26 ... Printing / Editing Monitoring Area 27 ... Work Area 28 ... Search Condition Storage Area 29 ... Access Flag File 30 ... Host Computer 32 ... Database

Claims (3)

(57) [Claims] 1. A search system for searching for a search target comprising at least one database, a condition setting computer for setting a search condition for the search target, a search condition storage means for storing the search condition, A flag is provided corresponding to each of a plurality of search areas obtained by dividing the search target into a predetermined size, and stores a flag indicating whether each search area is in a non-search state, a search state, or a search completed state. Flag storage means, a plurality of computers that operate independently of each other and perform a search of any one of the search areas according to the search conditions stored in the search condition storage means, and store the search results obtained in each computer. And a search result storage means, wherein each computer sets a flag in a non-search state to a search state and responds to the flag. A search area is searched, the obtained search result is output to the search result storage means, and a search cycle for setting the search status flag to the search completion status is executed, and all the unsearched flags are searched. A search system, characterized in that the search cycle is repeated until a completed state is reached. 2. A search cycle of a search area corresponding to the flag when a flag that is not set to the search completion state even if a predetermined time has elapsed after being set to the search state is set among the flags. The search system according to claim 1, wherein the search system is executed by a computer other than a computer that is executing a search cycle of the search area. 3. The respective computers search the search target via a communication line.
Alternatively, the search system described in 2.