JPH08212118A - Data base processing system - Google Patents

Abstract

PURPOSE: To easily perform the correction of a control part for writing/reading data when the in-record position or size of these data is changed in a system for reading/writing data from terminal equipment to a disk device existent at a host. CONSTITUTION: When performing access from a terminal 10 for accessing a host 20 equipped with a disk device 24 storing a file including plural records to any specified record in that file at the system provided with the host 20 and the terminal 10, information expressing the in-record position and size of access object data is included in retrieval data including the access command of the file and a retrieval key and those data are transmitted to the host. At the host where the retrieval data are received, based on the information expressing the in-record position and the size, the access object data of the record corresponding to the retrieval key are accessed and the accessed result is returned to the terminal 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a database processing system, and more particularly, from a terminal device via a communication line or the like.
In a database processing system that reads / writes data from / to a disk device connected to a host computer, when a record format is changed, it is not necessary to modify the host-side related program and only the terminal-side work is necessary to maintain the related program. The present invention relates to a database processing system capable of simplifying work.

[0002]

2. Description of the Related Art When a disk device of a host computer (hereinafter, simply referred to as a host) is read from or written to a terminal device, a control unit in the terminal device inputs a command name for reading or writing the disk device, and the command name To the host, receive the result data transferred from the host, and output it on the display screen.

On the other hand, the control unit in the host receives the command name from the terminal device, determines the position and size of the data in the record format to be read and written by the control unit based on the command name, and obtains it. The target data is read and written, and the resulting data is transferred to the terminal device.

[0004]

In the system in which the host receives the command name from the terminal device and then the host itself judges the position and size of the record data to be read and written, a new function is provided. If the position or size of the data in the record to be read or written is changed due to the support or functional improvement of the system, there is a problem that the system maintenance is bad because the correction work occurs in both the control unit on the terminal device side and the control unit on the host side. It was

For example, in a database search system, when an attempt is made to support a function of shifting from a conventionally used summary screen to an analysis code input screen as a sub screen, not only the program on the terminal device side is changed, It was necessary to perform the complicated work of changing the record format of the database on the host side (adding the "analysis code" area).

An object of the present invention is, in a system for reading / writing data from / to a disk device existing in a host from a terminal device, when a position in a record of data or a size change occurs, a control unit for reading / writing this data. It is to provide a database processing system that can easily perform the correction work of.

Another object of the present invention is to provide a database processing system capable of coping with a change in the position or size of the above-mentioned data only by changing a parameter on the terminal device side.

[0008]

In order to achieve the above object, a database processing system according to the present invention comprises a host computer having a storage device storing a file containing a plurality of records, and a communication line for the host computer. In a database processing system equipped with a terminal device accessed via, when accessing a specific record in the file from the terminal device, in the terminal device, search data including an access command and a search key of the file Including the information indicating the position and size in the record of the access target data, the host computer, which has transmitted the search data and has received the search data, stores the position in the record and the position corresponding to the record corresponding to the search key. Based on the size information Access the access target data, characterized by returning the access result to the terminal device.

In this system, the terminal device is
When the access command is write, write data is included in the search data.

Further, preferably, the terminal device has a storage means for storing a record format definition parameter defining a record format of the file and a data designating parameter for specifying access target data, and the search is performed by combining both parameters. Create the data.

The storage device of the host computer is, for example, a disk device, and the host computer accesses the target data by acquiring the record position and size of the access target data in the file stored in the disk device. It has a disk device input / output control means for performing.

[0012]

According to the present invention, the search data to be transferred from the terminal device to the host is transferred to the host by including the record position and size of the access target data on the disk device of the host computer. It is possible to access the target data by extracting the record position and size of the data to be read / written from this search data without being aware of which data is read / written by the control unit.

Further, a record format definition parameter that defines the record format of a file on the disk device and a data specification that specifies which data is to be read and written are used to specify the position and size in the record of the data to be accessed on the disk device. It is specified by a combination of two parameters.

According to the present invention, the host only needs to operate in accordance with the position and size in the record of the access target data transferred from the terminal device, and it is not necessary for the host to judge and obtain them. The program change work in the host does not occur when the position or size of the data in the record is changed. Furthermore, since the terminal device side can deal with the problem only by changing the parameters, the program changing work in the terminal device does not occur.

[0015]

Preferred embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 shows a configuration example of a database processing system to which the present invention is applied. This system includes a host 20 and at least one terminal device 10 connected to the host 20 via a communication line 18. The communication line 18 is
It may be a LAN, a public line, or a dedicated line. The terminal device 10 includes an input unit 11 such as a keyboard, a control unit 12 including a central processing unit and a memory, a disk input / output control unit 13, and a disk device 1
4, a communication control unit 15, and an output unit 16 such as a display device and a printer.

On the other hand, the host 20 includes a communication control unit 21 and
It has a control unit 22 including a central processing unit and a memory, a disk input / output control unit 23, and a disk device 24. Each of these can be configured by an ordinary personal computer or workstation.

In the control unit 12 of the terminal device 10, the input unit 1
1 to a read / write request (command name) to the disk device 24 of the host 20, a search key for specifying a record, write data (in the case of a write request), and the like, and further to the disk via the disk input / output control unit 13. Data specification parameters and record format definition parameters for reading and writing only desired data are input from the device 14, and search data is automatically created based on these information. Therefore, even if the position or size in the record of the data to be read / written on the host 20 side is changed, it can be dealt with only by changing the parameter on the terminal device 10 side.
The programs on the 0 side and the terminal device 10 side do not need to be changed, and the maintenance work of the programs becomes easy.

FIG. 2 shows an example of automatic creation of search data in the terminal device 10. The control unit 12 in the terminal device 10
Search data 27 for automatically accessing a file (database) stored in the disk device 24 in the host 20 is automatically created based on the data specification parameter 25 and the record format definition parameter 26. The data designation parameter 25 includes a group name 251, which indicates a group of data to be read and written, an access target file name 252, a search key 253 for identifying the access target record, a data item name 254 in the record.
It consists of 255. Although two data item names are shown in this example, the number of data item names may be one or three or more. The data item name is, for example, 4-digit alphanumeric data, and a name that can be associated with the data item is used. The data designation parameter 25 is created by the program creator or the user according to the purpose of each search by the user.

Record format definition parameter 26
Is created in advance for each file and its file name 2
61, a control key 262 for designating a record to be accessed, and sizes 263 and 264 for each data item name in the record are defined.

The control unit 12 controls the parameters 25, 2 and
6 based on No. 6, the search data 28 in the case of a write request
And the search data 29 in the case of a read request. This automatically created search data is for communication line 1
8 to the host 20.

The search data 28 includes a command section 281 storing a write request command, a file name section 282 storing a file name, a search key section 283 storing a search key, and write data sections 284 and 288. Become. The write data sections 284 and 288 respectively have the in-record data positions 285 and 28 of the data.
9, data size 286, 290, and data 287, 291 to be written.

The search data 29 includes a command section 291 storing a read request command, a file name section 292 storing a file name, a search key section 293 storing a search key, and an in-record position 295 of data to be read. , 298 and read data sections 294 and 297 storing sizes 296 and 299. The position in the record of each data item can be obtained from the data item name and the size of each data item name in the record format definition parameter 26.

FIG. 5 shows a concrete example of the command name for the write / read request used in this embodiment. The commands are roughly classified into a write (write) for writing data to the disk file and a read (read) for reading the data in the disk file. More specifically, they are defined as shown in FIG. Where "FA"
Indicates a command for additional writing of data, "FU"
Indicates a command for updating (overwriting) data, "FR"
Indicates the reading of only one data item. Also, "FR
X "represents reading of data for a plurality of items, and" FD "represents deletion of data.

An example of the contents of the record format definition parameter 26 and the data designation parameter 25 before and after the change of the record format of the disk file in this embodiment will be described with reference to FIG. In this example, the record length is a fixed length of 155 bytes. Of course, the present invention is not limited to this.

The column 31 in FIG. 3 shows the parameter contents before changing the record format for a certain terminal. This record format definition parameter 26 is for the file name "JXXX", and its control key (CKEY) XXX is 10 bytes, the data item name "KYOU (common part)" is 100 bytes, and the data item name is " 45 bytes are allocated to "YOBI (spare)". The "control key" is a unique key for identifying one record in the database and is also called a "primary key".
The data specification parameter 25 in FIG. 3 shows an example of reading, in this case, the group name is "AAAAA", the file name of the access target is "JXXX", the maximum number of read items (TYPE) is 11, and the search key. Is "XXXX",
It is specified that only the data item name to be read is “KYOU” and the search condition “EQ” with the same search key “XXXX” is searched. In addition, "TYPE = 1
The first term on the right side of "1, 0, R" is the maximum number of transfer cases, the second term is the start transfer data transmission start point ("0" is from the beginning), and the third term is the necessity of setting the number of hits (R: not required, F: required).
The “LINK =” clause is information defined in the database definition information of the host, and CKEY (control key) or LX01 to LXnn (index keys 1 to nn, where nn is a number) is specified on the right side thereof. . The index is used when performing a variety of condition searches by designating an arbitrary data item in a record in the database, which makes it possible to efficiently search for a specific data item. The “KEY =” phrase is information defined by the database definition information on the terminal side. When actually searching the database on the host, the "control key" or "index key" is essential information. Usually, the search key corresponding to the information designated by "LNK =" is designated by the data designation parameter. Thereby, the database definition information on the terminal side and the database definition information on the host side are associated with each other. The LNK determines the search order in the host. An example of specifying the control key and the index key will be described later with reference to FIG. "CO
The first term on the right side of “MP = XXXX, A, EQ” is a search key,
The second term is a logical operator of multiple conditions (A: AND, O: O
R, where A is used when there is only one condition), and the third term indicates conditions (EQ: equal, NE: not equal, GE: greater than or equal, etc.).

On the other hand, as shown in the column 32 of FIG. 3, the terminal A shows an example in which a new data item “analysis code A” is added to the corresponding record of the file as a data item. In this example, compared to before
In the record format definition parameter 26, a spare data item 45 bytes to a 20-byte data item "BUNA" is newly allocated to this added item. Therefore, the data item "YOBI" is reduced to 25 bytes. Along with this, data specification parameter 2
A data item name “BUNA” is added to item 5.

As shown in the column 33 of FIG. 3, in the terminal B, a new data item "analysis code B" is added as a data item to the corresponding record of the file. In this example, as compared to before the change, in the record format definition parameter 26, a spare data item 45 bytes to 25 bytes of a data item “BUNA” is newly allocated. Moreover, the analysis code B is arranged after the spare. The data item "YOBI" has been reduced to 20 bytes. Along with this, a new data item name “BUNB” is added to the data designation parameter 25.

The analysis codes A and B are assigned to the terminals A and B so that they do not overlap each other in the record.

The restrictions on defining the record format for each terminal are as follows.

(1) Match the record length with the database definition information of the host.

(2) The positions and lengths of the "control key" and the "index key" are matched with the database definition information of the host.

(3) Define different data items so that they do not overlap each other. When overlapping, define a code area that can identify each of them as exclusive data, and read and write only your own record. This avoids destroying the opponent's record.

FIG. 7 shows an example of designation of control keys and index keys. In this example, CKEY and XXXX correspond, and index 1 (LX01) and LD01 correspond. Therefore, when the search key is XXXX, the data specification parameters are LNK = CKEY, KEY = XX
When XX is defined and the search key is LD01, LNK = L
X01 and KEY = LD01 are defined. In the example of FIG. 3, the LNK name is CKEY and the search key is XXXX, the search is performed in the CKEY order (registration order), and the data with the same XXX is read.

Next, FIG. 4 shows a specific processing procedure for reading and writing a disk file in this embodiment. FIG.
4B shows a processing procedure at the time of writing, FIG. 4C shows a processing procedure at the time of reading, and FIG. 4A shows a place (means) where each processing step is executed.

The processing procedure at the time of writing will be described with reference to FIG. First, in the terminal device 10, the user inputs a write request, a search key, and write data from the input unit 11 (41). The write request also includes information designating the file to be accessed. If not, it is assumed that the target file has been specified before starting this processing. The information (name) for specifying the write request and the used data designating parameter, the search key, the write data, and the search condition are input to the input unit 1 of the terminal device.
1 to the control units 12 and 13 (42). In the present embodiment, the “used data designation parameter name” and the “search condition” are obtained based on the write request input in step 41. That is, the writing screen is selected, and the “use data designation parameter name” is determined for each writing screen. Further, the search condition data is input, and the "search condition" is determined based on this. The “search condition” is prepared in advance for each writing screen. On the other hand, the data specification parameter 25 and the record format definition parameter 26 are read from the disk input / output control unit 13 (43). Therefore, the control unit 12 checks the data consistency (44) and displays an error if there is a problem (46). If there is no problem, search data is automatically created (45). That is, "FI described in the use data specification parameter
The file name is determined from the LE = "phrase, and the record format definition parameter to be used is determined from this file name.
Further, the position and size of the data to be written are determined from these parameters, and the search data for writing is created. That is, the file name, search key and search condition, position and size of data to be written, and write data are set in the search data 28 (FIG. 2). In addition, from the write request to the write command name (here, F
A: Add data) is set and set in the search data. The search data created in this way is transmitted from the communication control unit 15 to the host 20 (47).

In the host 20, the communication control unit 21 receives the write search data (48), and the control unit 22 analyzes the write search data (49). That is,
Detects that the write command name is append data,
Also, the write target file name, the search key and the search condition, the position and size of the data to be written, and the write data are confirmed, and the data is written to the file of the disk device 24 via the disk input / output control unit 23. And prepare to send back the writing result (success / failure of writing). Next, the communication control unit 2
According to 1, the writing result is transmitted to the terminal device 10 (50). This is received by the communication control unit 15 in the terminal device 10 (51), and the writing result received by the control unit 12 is edited for display and displayed on the output unit 16 (5).
2).

The steps 53 to 64 of the processing at the time of reading in FIG. 4C are the same as those in FIG. 4B except that the write data is not input from the terminal device 10 and the read data is returned from the host. ) Is the same as the processing procedure at the time of writing.

Preferably, while the host 20 is accessing the disk file, the display screen of the output unit 16 of the terminal device 10 displays that the disk file is being accessed.

A specific example of access to a disk file (database) in the host 20 will be described with reference to FIG. Now, it is assumed that the file name database in the disk device 24 is stored. This database stores ten records 1 to 10 in the illustrated example. In each record, the search key data is stored at the beginning, the data item name "data 1" is stored at the record position 1, and the data item name "data 2" is stored at the record position 2. There is.

As an example of writing to this database, "123" is written in the data item "data 1" and "ABCD" is written in the data item "data 2" for the record whose search key is "A". It is assumed that search data is received. For this search data, as shown in the figure, “123” is written in position 1 of records 1, 4 and 7 having the search key “A”, and “ABC” in position 2.
D "is written. As an example of reading, for a record whose search key is" B ", if" data 1 "and" data 2 "are specified as the data item names to be read, record 2 that has" B "as the search key And the data of record 8 (“456EFGH” and “78, respectively)
9IJKL ") is read.

[0042]

As described above, according to the present invention, a change in the position or data size of data to be read / written can be dealt with by only changing some parameters of the terminal device, so that the maintainability is remarkably improved. Furthermore, it becomes possible to easily define the dedicated data for each terminal device.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration example of a database processing system to which the present invention is applied.

FIG. 2 is an explanatory diagram of an example of creating search data according to the embodiment of this invention.

FIG. 3 is an explanatory diagram showing an example of changing various parameters before and after changing a record format in the embodiment.

FIG. 4 is a flowchart showing a processing procedure at the time of writing and reading in the embodiment.

FIG. 5 is an explanatory diagram of a specific example of a command according to the embodiment.

FIG. 6 is an explanatory diagram showing a specific example of access to a disk file in the embodiment.

FIG. 7 is an explanatory diagram of a control key and index key designation example in the embodiment.

[Explanation of symbols]

10 ... Terminal device, 11 ... Input unit, 12 ... Control unit, 13 ...
Disk input / output control unit, 14 ... Disk device, 15 ... Communication control unit, 16 ... Output unit, 18 ... Communication line, 20 ... Host computer, 21 ... Communication control unit, 22 ... Control unit, 2
3 ... Disk input / output control unit, 24 ... Disk device, 25
... data designation parameter, 26 ... record format definition parameter, 27 ... search data.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yukio Motoyoshi 2-14-6 Kanda, Uchikanda, Chiyoda-ku, Tokyo Inside Ritsuden Electronic Service Co., Ltd. (72) Motoharu Morisaka 2-14, Uchikanda, Chiyoda-ku, Tokyo No. 6 Nitrate Electronic Service Co., Ltd.

Claims (4)

[Claims] 1. A database processing system comprising: a host computer having a storage device storing a file containing a plurality of records; and a terminal device for accessing the host computer via a communication line. When accessing a specific record in the file, in the terminal device, the search data including the access command and the search key of the file, including the information indicating the position and size in the record of the access target data, to the host computer The host computer, which has transmitted the search data, accesses the access target data of the record corresponding to the search key based on the information indicating the position and size in the record, and outputs the access result. Is returned to the terminal device Database processing system for the butterflies. 2. The database system according to claim 1, wherein the terminal device includes write data in the search data when the access command is write. 3. The terminal device has a storage means that stores a record format definition parameter that defines a record format of the file and a data designation parameter that specifies access target data, and combines both parameters to retrieve the search data. The database processing system according to claim 1, which is created. 4. The storage device of the host computer is a disk device, and the host computer acquires the target data position by acquiring the position and size in the record of the access target data in the file stored in the disk device. The database processing system according to claim 1, 2 or 3, further comprising a disk device input / output control means for accessing.