JPH07129607A - Database system data communication recording method - Google Patents

Abstract

(57) [Abstract] [Purpose] In the data communication recording method of the database system, the communication cost is low, and the search speed is high.
It is possible to automatically update and delete data. [Structure] In a server / client type database system, a search terminal is provided with a sub-recording device divided into n areas, and a database that has the effect of reducing communication costs by controlling with a recording area allocation device Provide the system.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a server / client type database system data communication recording method via a communication line.

[0002]

2. Description of the Related Art In a server / client type image database system, the server centrally manages (records) data.
However, a general method is to transmit the corresponding image data in response to a request from the search terminal and display it on the monitor on the terminal side.
If these servers and multiple search terminals are connected within the same business site, for example, Ethernet or IEEE8.0.2.3, there is no hindrance to operation except that communication efficiency (speed) decreases. However, when the search terminal is installed in a remote place, large amount of image data is frequently transmitted and received via the ISDN line, which causes drawbacks such as increase in communication cost and disconnection of the line. It was Therefore, it is conceivable to provide a recording device also on the terminal on the remote side so as to record a part of the data of the server. As a prior art, JP-A-63-54670 and JP-A-4-283866 are available.
Therefore, the same recording device as the server is provided on the terminal side, only the index is searched for, and the actual data is obtained from the recording device on the terminal side.

[0003]

However, in the conventional method of recording a part of the data of the server by providing a recording device also on the remote side terminal, what is recorded as a part, At what point you want to delete that data,
However, there was a problem that the search time would rather be delayed if carelessly recorded.

Also, in the above-mentioned prior art, although the speed is improved, there is a problem that the data amount is wasted because it has the same data as the server.

Further, neither of the above-mentioned prior arts mentions the erasing mechanism, and there has been no efficient data recording method proposed by the inventor of the present application.

The present invention has been made to solve the above-mentioned conventional problems, and is a data communication record of a database system that has a low communication cost, a high search speed, and can automatically update and delete data. The purpose is to provide a method.

[0007]

SUMMARY OF THE INVENTION The present invention is a data communication of a database system having a main recording device for recording a plurality of data and one or more search terminals connected to the main recording device via a communication line. In the recording method, in the search terminal, a sub recording device having a smaller capacity than the main recording device,
By providing a recording area allocating device, dividing the sub recording device into n areas, and writing, reading, and deleting the received data in accordance with the area indicated by the recording area allocating device, It has been achieved.

According to the present invention, the received data is deleted from the oldest written area in time and the newest written area is searched. The above object is achieved.

[0009]

In the recording method, the sub-recording device having a capacity smaller than that of the main recording device is provided on the search terminal side, and the data once received from the line is recorded on the remote terminal side to reduce the communication cost. Careless recording will slow down the search time. (2) Two important issues are how to delete when the small capacity is full. The inventor pays attention to this point. And make this proposal.

That is, according to the present invention, in a database system in which a main recording device and a search terminal are connected via a communication line, a sub recording device having a capacity smaller than that of the main recording device is provided for each search terminal at a remote place. , It is further divided into n areas, and the data once received from the main recording device is recorded in one of the above areas, and when the next search occurs, the sub recording device is searched first and the data exists. Since only the missing data is received from the main recording device via the communication line, the communication cost can be reduced, the traffic can be reduced at the same time, and the line can be easily connected.

Further, a recording area allocating device for managing n areas is provided, and writing to the sub-recording device (in case the area is full is deleted before writing is performed according to an instruction of the recording area allocating device). )), Or to search.

If the oldest written area is deleted first, the oldest area (data) is automatically deleted in order even if the sub-recording device is full, and the newest area is deleted. Data for n areas is always retained.

Further, in the case of searching, the searching speed can be increased by searching sequentially from the newly recorded divided areas.

[0014]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing an outline of the entire image database system.

In FIG. 1, reference numeral 1 is a server, which is composed of a workstation or the like. A main recording device 2 stores a character database (image file names are stored in records) and image data. Image data can be input from a scanner, high-definition camera, etc., but here 320 × 240.
230 Kbytes of pixel full-color image (K
B) is compressed and stored to about 1/20 according to the JPEG method. Therefore, if the main recording device 2 is a hard disk (hereinafter abbreviated as HD) of about 2 gigabytes (hereinafter GB), 100,000 or more image data can be recorded.

Reference numeral 3 is a communication line. Since the search terminal is located at a remote place here, the ISDN INS net 64 is provided.
Are using. Compressed image data is about 12KB, so when sending and receiving over a 64Kbps line, at least 1.5 seconds is required for each actual data transfer (actually, more time is required). .

Reference numeral 4 is a search terminal, which is usually composed of a personal computer. 5 is a sub recording device connected to this personal computer.
HD of about 0 megabyte (hereinafter referred to as MB) is also used. A plurality of combinations of 4 and 5 are shown in other dotted lines in a dotted line.

FIG. 2 is a block diagram showing the system configuration of the system within the dotted line.

In FIG. 2, 3 is a communication line, 5 is a sub-recording device, and 6 is a control device which is a CPU of a personal computer. Reference numeral 7 is a display device capable of displaying full color. Reference numeral 8 is a communication control device, 9 is a recording area allocation device, and 10 is a system bus.

When the file name of the image data corresponding to the search is obtained, the present system does not directly access the server 1 and the main recording device 2, but searches the sub-recording device 5 once and exists. If not, the image data is received from the communication line 3 via the communication control device 8 (generally available ISDN board), the control device 6 expands the image, and the display device 7 performs full-color display. Further, writing is performed in the sub recording device 5.

FIG. 3 is an image diagram of the sub-recording device 5, and in the present embodiment, each 50 MB HD is divided into eight partitions with n = 7.

Further, FIG. 4 shows the recording area allocating device 9, 5a is an area which has already been received and is full, and 5b is an area which is currently in use (writing is to be performed). Use register n.

Besides, 14 search registers R and 15
The write register W of FIG. 1 is implemented by software.

FIG. 5 is a flowchart showing the operations of the search terminal and the recording area allocation device. Since the W register 15 increments and the R register 14 cyclically operates while decrementing, the areas to be written, searched (read), and deleted are completely allocated.

This operation will be described in detail below.

When the file name is obtained in step 100 of FIG. 5, n is entered in the R register 14 in step 102, and the area indicated by the R register (simply called the R area) is searched in step 104. If it is determined in step 106 that there is no file, the process proceeds to step 108 and the R register 14 is decremented by 1. R in step 110
Is less than 0, 7 is put into R in the next step 112, and if R is not less than 0, the value of R is left unchanged,
In step 114, it is determined whether R = n.

If R = n is not satisfied, the process returns to step 104. If R = n, the process proceeds to the next step 116 to receive the corresponding file, and at step 118, the W register 15 is updated to n.
Put in.

In step 120, it is judged whether or not the capacity is full. If the capacity is full, the W register 15 is incremented by 1 in the next step 122. If W is greater than 7 in step 124, W is set to 0 in step 126, and if W is not greater than 7, W is left as it is. If it is determined in step 128 that the capacity is full, the W area is deleted in step 130. In step 132, data writing is performed.

If it is determined in step 120 that the capacity is not full, data writing is performed in step 132. Finally, in step 134, the image data is displayed and the process ends.

On the other hand, if it is determined in step 106 that a file exists, the data is read in step 136,
In step 134, the image data is displayed and the process ends.

As described above, according to this embodiment, since the latest data that has been received once is recorded in the sub-recording device, the hit rate at the time of retrieval is generally high.

[0033]

As described above, according to the present invention,
A search terminal at a remote location has a smaller capacity than the main recording device.
Since the sub-recording device divided into n areas is provided and the recording area allocating device sequentially records, searches, and deletes the data, the communication cost can be reduced.

Further, by deleting from the oldest written area in time and searching from the newest written area, the retrieval speed is fast and old data is automatically deleted. There are also effects such as being done.

[Brief description of drawings]

FIG. 1 is a block diagram showing the entire image database system of this embodiment.

FIG. 2 is a block diagram showing a configuration of a search terminal and a sub-recording device according to this embodiment.

FIG. 3 is an explanatory diagram of a sub-recording device divided into n areas.

FIG. 4 is an explanatory diagram showing a configuration of a recording area allocation device according to the present embodiment.

FIG. 5 is a flowchart showing the operations of the search terminal and the recording area allocation device according to this embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Server 2 ... Main recording device 4 ... Search terminal 5 ... Sub recording device 9 ... Recording area allocation device

Claims (2)

[Claims] 1. A data communication recording method for a database system, comprising: a main recording device for recording a plurality of data; and one or more search terminals connected to the main recording device via a communication line. A sub-recording device having a smaller capacity than the main recording device, and a recording area allocation device, dividing the sub-recording device into n areas, and writing received data according to the area indicated by the recording area allocation device. , A data communication recording method for a database system, characterized in that the data is read and deleted. 2. The method according to claim 1, wherein among the received data, the data in the area written earliest in time is deleted, and the data in the area written most recently is searched. A data communication recording method of a characteristic database system.