JPH0546450A - Multihost data base access device - Google Patents

Abstract

PURPOSE:To enable plural host computers different by access methods to access data bases by the same operation procedures. CONSTITUTION:A host communication part 20 performs connection to and disconnection from a host computer designated by a user and start and data access of different data base management systems, and a data conversion part 23 converts reception data to a common format at the time of receiving data having the format peculiar to the computer of the other party by the host communication part 20 and converts data having the common format to be transmitted to data, which the computer of the other party can discriminate, at the time of transmission to this computer. An input/output data editing part 27 is provided, and data inputted from a data input device 31 is edited to the common format and is transferred to the data conversion part 23, and reception data converted by the data conversion part 23 is edited on a picture format and is displayed on a display device 32.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-host database access device for accessing databases on a plurality of host computers.

[0002]

2. Description of the Related Art Usually, a database on a host computer is often provided with a pair of simple search tools that make the database accessible. However, this simple search tool depends on the database of the host computer, and when the host computer or database changes, a tool unique to it is required.

Regarding the database access device (terminal device) for accessing the database, knowledge of how to use the database and the host computer is required to use the device. Further, this type of database access device is developed according to the function of the target database, and therefore cannot be handled by other databases or computers with different usage methods.

[0004]

As described above, in the conventional database access device, since the usage method differs depending on the target host computer or database, when necessary data is stored in a plurality of host computers, , The data had to be accessed by different operation methods using different database access devices.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a multi-host database access apparatus capable of performing database access to a plurality of host computers having different access methods by the same operation procedure. is there.

[0006]

According to the present invention, there is provided a host communication means for performing transmission / reception processing adapted to a host computer with each of a plurality of host computers having a unique database accessed by a unique access method. And input data such as request information to be sent to one of the plurality of host computers, which is input by the data input means, is edited into data of a common format irrelevant to the other computer, and the received data is edited to output the screen. Input / output data editing means to be performed, and input data in a common format edited by the input / output data editing means are converted into data that can be identified by the partner computer, output to the host communication means, and received by the host communication means. The data in the format unique to the partner computer is converted into the received data in the common format and then input / output. Is characterized in that a data conversion means for notifying the data editing means.

[0007]

In the above configuration, when input data such as request information (connection request, database access execution request, disconnection request, etc.) to be sent to one of the plurality of host computers is input from the input means, the input data is input. Is passed to the input / output data editing means. The input / output data editing means converts the input data from the input means into data in a common format irrelevant to the other computer (data of a connection command common to each host computer in the case of a connection request and data of a connection command in the case of a database access execution request). Edit to a database access execution command common to the host computer and pass it to the data conversion means. The data conversion means converts the data in the common format passed from the input / output data editing means into data that can be identified by the partner computer (in the case of a common connection command, a connection command unique to the partner computer) for host communication. Hand to means. The host communication means generates transmission data in which internal data peculiar to the partner computer is added to the data passed from the data conversion means, and sends it to the partner computer.

The host computer performs the processing requested by the data (the connection processing if the data includes the connection command, the database access processing if the database access execution command) by the data sent from the data communication means, A response message containing the processing result and having a format unique to the host computer is sent to the host communication means. Upon receiving the response message sent from the host computer, the host communication means deletes the internal data peculiar to the partner computer from the message and passes the deleted data to the data conversion means as received data. The data conversion means converts the received data passed from the host communication means into a common format and notifies the input / output data editing means of the reception. As a result, the input / output data editing means compares the received data converted by the data converting means with the information of the screen format contained therein, and displays it at the screen position indicated by the same format.

[0009]

1 is a block diagram showing the configuration of a system equipped with a multi-host database access device according to an embodiment of the present invention.

In FIG. 1, reference numerals 1a to 1c denote unique databases, a database management system (DBMS) for managing the databases, and a dictionary (not shown) in which a database name, a list of data item names, etc. are stored. ) Is a host computer having a well-known configuration. Here, each of the host computers 1a to 1c
Each DBMS is structured query language (SQ
L) is supported, and the database can be accessed (searched) by accepting this SQL. It is also assumed that the dictionary unique to each of the host computers 1a to 1c can be searched by a common command. As is well known, SQL uses a select clause including an output item name, a calculation item, and an expression, a from clause including a database name, and a where clause including a combination of a use data item name, an extraction condition, a search key, and a condition. Composed.

Reference numeral 2 is a multi-host database access device for accessing the host computers 1a-1c in the same operating procedure. The multi-host database access device 2 is composed of, for example, a personal computer.

Multi-host database access device 2
Connects to the host computer 1i (i is any of a to c) specified by the input from the data input / output device 30 described later at the start of the process, and the host computer 1i at the time of executing the process.
It has a host communication unit 20 that transmits and receives data to and from the host computer 1i and disconnects from the host computer 1i at the end of processing. The host communication unit 20 has a common communication function that does not depend on the host computers 1a to 1c, and a communication interface unit (hereinafter, referred to as a communication interface unit that controls basic communication with the host computers 1a to 1c).
21) and each host computer 1a-1
A transmission / reception data editing unit 22a, which is provided for each c and edits data transmitted / received to / from a corresponding host computer
22c.

Multi-host database access device 2
Is also provided for each of the host computers 1a to 1c, converts the data passed from the transmission / reception data editing units 22a to 22c into a common format that does not depend on the host computer, and transmits the transmission data to the host computers 1a to 1c. Has a data conversion unit 23 for converting the data into a format unique to the. The data conversion unit 23 includes a text conversion unit 24a to 24c that issues a common command based on an instruction from the data input / output device 30, and a common command issued by the text conversion units 24a to 24c to a host computer. It has command generation units 25a to 25c for converting commands unique to 1a to 1c.

Multi-host database access device 2
In addition, the data to be output to the screen and the host computer 12i
Common data storage unit 26 for storing data to be transmitted to a computer in a common format that does not depend on the computer 12i.
And an input / output data editing unit 27 which forms an interface between the data conversion unit 23 and the data input / output device 30 and controls the editing of the input / output data. The input / output data editing unit 27 changes the menu screen according to the data input from the data input / output device 30 and inputs the data input from the data input / output device 30 into a format suitable for the processing of the data conversion unit 23. The data editing unit 28 and the common data storage unit 2
6 has a screen output section 29 for taking out data to be displayed on the screen from the data stored in 6 and outputting it to a display device 32 described below in accordance with an internal screen format.

Multi-host database access device 2
Further has a data input / output device 30 as a terminal device (data input / output terminal). The data input / output device 30 is
A data input device 31 such as a keyboard and a display device 32 such as a CRT display or a liquid crystal display
And are integrated.

Next, the outline of the processing procedure when the database of the host computer 1a is accessed from the multi-host database access device 2 shown in FIG. 1 will be described with reference to the flowchart of FIG.

First, when the user of the multi-host database access device 2 wants to access the database of the host computer 1a, he / she uses the data input / output device 30 (data input device 31 thereof) to establish a connection with the host computer 1a. Perform input operation to request. As a result, the database access device 2 transmits the transmission data including the connection request command to the host computer 1a, and the connection request is made (step S1).

Upon accepting this connection request, the host computer 1a returns a response to that effect to the database access device 2. The response content is displayed on the display device 32 of the data input / output device 30 (step S2).

When the user confirms from the display screen of the display device 32 that the database access device 2 is connected to the host computer 1a, the data input device 31 of the data input / output device 30 is used to connect the host computer 1a. Perform an input operation for requesting activation of the dictionary of 1a.
As a result, the database access device 2 transmits the transmission data including the dictionary activation request command to the host computer 1a, and the dictionary activation request is made (step S3).

When the host computer 1a receives this activation request, it activates the dictionary (sets it in a dictionary searchable state) and returns a response to that effect to the database access device 2. The content of this response is displayed on the display device 32 of the data input / output device 30 (step S4).

When the user confirms that the dictionary of the host computer 1a has been activated from the display screen of the display device 32, the data input device 31 of the data input / output device 30 is confirmed.
Is used to perform an input operation for requesting a dictionary search of the connection destination host computer 1a. This allows
Transmission data including a dictionary search request command is transmitted from the database access device 2 to the host computer 1a, and a dictionary search request is made (step S5).

When the host computer 1a accepts this search request, it searches the dictionary, and if it is a search request for a database name list, it searches the database name list, and if it requests a data item name list search, it searches the data item name list. , And returns a response message including the list data to the database access device 2. This list data (database name list or data item name list)
Is displayed on the display device 32 (step S6).

Here, the user operates the data input device 31, selects and designates the database name to be accessed when the database name list is displayed, and wants to access when the data item name list is displayed. Select and specify the database name.

When the database access device 2 receives the selection designation input from the data input device 31 (step S7), it selects the designated database name or data item name (use data item name), and selects the selected contents. The data is stored in the common data storage unit 26 (step S8). Also, the database access device 2 accepts selection and designation input from the user using the data input device 31 by talking with the user through the display device 32 regarding the extraction condition and the search key necessary for database access. ,
The data is stored in the common data storage unit 26.

When the user operates the data input device 31 to request execution of database access (search), the database access device 2 accepts the request (step S9) and is stored in the common data storage unit 26. Database name (specified by the user), usage data item name,
SQL based on various information such as extraction conditions and search keys
A sentence (structured query language) is automatically assembled and generated (step S10). When the SQL statement is generated, the database access device 2 transmits the transmission data including the database activation command to the host computer 1a, and the database activation request is made (step S11).

Upon receipt of this activation request, the host computer 1a activates its own DBMS (database management system) to bring it into a database searchable state, and returns a response to that effect to the database access device 2. As a result, the database access device 2 sends to the host computer 1a the transmission data including the SQL statement (as a database access command) generated in step S10 to the host computer 1a, and a database access request is made (step S12).

The host computer 1a passes this database access request (SQL sentence) to its own DBMS. As a result, the DBMS in the host computer 1a accesses its own database according to the received database access request (SQL sentence) and extracts the requested data.
This data is transmitted from the host computer 1a to the database access device 2 and displayed on the display device 32 (step S13).

As described above, according to the present embodiment, even if the user has no knowledge of programming or database,
A SQL statement for making a common inquiry to the DBMS of the host computer regardless of the difference between the host computer and the database, that is, database access, simply by performing a necessary selection operation while talking with the database access device 2 through the display device 32. The command is automatically generated and desired data can be extracted.

Even if a common inquiry can be made to the DBMS of each host computer by the above SQL statement, the transmission data including the SQL statement (database access command) differs depending on the host computer. The same applies to the transmission data including the connection request command described above. In the present embodiment, the transmission data including such a command can be automatically generated without the user being aware of the type of the host computer and the format of the command. This will be described in detail with reference to a connection request to the host computer 1a and a dictionary search request as an example.

First, the operation when a connection request is made to the host computer 1a will be described with reference to the operation explanatory diagram of FIG. When the user of the multi-host database access device 2 wants to access the database of the host computer 1a, he / she uses the data input / output device 30 (the data input device 31 thereof) to request the connection with the host computer 1a. And perform the following operations. That is, the user inputs his / her ID (identifier) and password and performs an operation for designating the host computer 1a.

As a result, the host computer connection request 41 is input from (the data input device 31 of) the data input / output device 30 to (the input data editing unit 28 of) the input / output data editing unit 27, as shown in FIG. To be done. The host computer connection request 41 also includes the user ID and password. The contents of the user's operation for the above-mentioned connection request are common regardless of the request-destination host computer.

Upon receipt of the host computer connection request 41 input from (the data input device 31 of) the data input / output device 30, the input / output data editing unit 27 (the input data editing unit 28) receives data from the host communication unit 20. Which of the module groups having different functions to be used for each host computer in the conversion unit 23 is determined according to the connection request 41.
Then, the input / output data editing unit 27 sets the execution right 42 for the determined module group as shown in FIG. Here, the execution right 42 is set for the module group of the transmission / reception data editing unit 22a, the text conversion unit 24a, and the command generation unit 25a corresponding to the host computer 1a. After that, unless a new host computer connection request (41) is given from the data input / output device 30, the set execution right 42 is held.

Next, the input / output data editing unit 27 (the input data editing unit 28 thereof) corresponds to the transmission / reception data editing unit (here, the transmission / reception data editing unit 22a) of the module group to which the execution right 42 is set. Host computer (1a)
Host computer connection instruction 43 for instructing connection with
To the text conversion unit 24a of the data conversion unit 23.

Upon receiving the host computer connection instruction 43, the text conversion unit 24a issues a common host computer connection command (host computer connection common command) 44 corresponding to the instruction 43 (regardless of the host computers 1a to 1c). It is issued to the generation unit 25a.

The command generator 25a internally has a command to be actually output to the host computer 1a, including the execution procedure of the command, corresponding to various common commands generated by the text converter 24a. .. When the command generation unit 25a receives the host computer connection common command 44 from the text conversion unit 24a, the command 44
A host computer connection command 45 (including a user ID and password) for the host computer 1a corresponding to the above is generated, and the transmission / reception data editing unit 22a of the host communication unit 20 is generated.
Pass to.

In the present embodiment, transmission / reception between the multi-host database access device 2 and the host computers 1a-1c is performed in 8-bit units, and the most significant bit is used as a parity bit for parity check. It has become.

However, the JIS alphanumeric / kana code is 8
Composed of bits. Here, the most significant bit of the alphanumeric code is "0" and the most significant bit of the kana code is "1".
Therefore, if the most significant bit is used as a parity bit and the remaining 7 bits are treated as an ASCII code, the host computer 1a to 1c cannot correctly recognize the code string including the kana code.

Therefore, normally, a start code indicating the beginning of the kana code string is added immediately before the kana code string (the string of the kana code in which the most significant bit is replaced by the parity bit) in the transmission data, and the same code string is added. An end code indicating the end of the kana code string is added immediately after, and each code sandwiched between these special codes is supplemented with "1" in the most significant bit (that is, in the code area on the JIS code table). (By shifting) so that it can be recognized as the original kana code.

The above two special codes differ depending on the host computer. Therefore, when the transmission / reception data editing unit 22a receives a command for the host computer 1a (here, the host computer connection command 45) from the command generation unit 25a, it adds a special code peculiar to the host computer 1a to the required portion of the command, Further, detailed data necessary for transmission / reception to / from the host computer 1a is added, that is, internal data peculiar to the host computer 1a is added to the command.
The data is sent to the kernel unit 21 as transmission data to a.

Therefore, when the host computer connection command 45 is given from the command generator 25a as described above, the host computer 1a responds to the command 45.
The transmission data 46 (to the host computer 1a) to which the internal data peculiar to is added is sent from the transmission / reception data editing unit 22a to the kernel unit 21. When the kernel unit 21 receives the transmission data 46 from the transmission / reception data editing unit 22a,
The same data 46 is transmitted as it is to the host computer 1a as transmission data 47.

When the host computer 1a receives the transmission data 47 from the kernel section 21, it performs a parity check, and if there is no error, deletes the above internal data,
Furthermore, the ASCII code is set to JIS for the kana code string.
Perform the operation to return to the code. And the host computer 1a
As in the present embodiment, when the data 47 that has been subjected to the above operation includes a host computer connection command, the user ID and password attached to the command confirms that the corresponding user is valid. Check to see if you are a user. As a result, when the host computer 1a determines that the user is a legitimate user, the host computer 1a uses the transmission data indicating that it (the host computer 1a) and the multi-host database access device 2 can be connected to the legitimate user. If it is determined that the user (host computer 1a) is not connected to the multi-host database access device 2, the transmission data indicating that the host computer 1a and the multi-host database access device 2 cannot be connected is returned to the kernel unit 21 as a response message 48. Upon receiving the response message 48 returned from the host computer 1a, the kernel unit 21 passes it as received data 49 to the transmission / reception data editing unit 22a as it is.

When the transmission / reception data editing unit 22a receives the reception data 49 from the kernel unit 21, the transmission / reception data editing unit 22a deletes the internal data specific to the host computer 1a from the data 49 and passes it as the reception data 50 to the command generation unit 25a.

When the command generation unit 25a receives the reception data 50 from the transmission / reception data editing unit 22a, if one command (the host computer connection common command 44 in this case) previously received from the text conversion unit 24a ends,
The received data 50 is passed to the text converter 24a as received data 51.

The text converter 24a converts the received data 51 passed from the command generator 25a into a format common to the multi-host database access device 2 and stores the received data 52 in the common data storage 26 as well as the received data 52. A reception notification 53 indicating that is sent to (the screen output unit 29 of) the output data editing unit 27.

Input / output data editing unit 27 (screen output unit 2)
9), when receiving the reception notification 53 from the text conversion unit 24a, retrieves the corresponding reception data from the common data storage unit 26, and responds to the internal host computer connection request (indicates whether connection is possible) screen format. The same data (response message) is set therein to create a screen image 54, which is output to (the display device 32 of) the data input / output device 30 and displayed on the screen.

Next, the operation at the time of the dictionary search request in the configuration of FIG. 1 will be described with reference to the operation explanatory diagram of FIG. Now, it is assumed that the user uses (the data input device 31 of) the data input / output device 30 to perform an operation for requesting a dictionary search to the host computer 1a. As a result, the data input / output device 30 (data input device 3
As shown in FIG. 4, the dictionary search request 61 is input from (1) to the input / output data editing unit 27 (the input data editing unit 28 thereof). Note that the operation content of the user at this time is also the same as in the case of the host computer connection request described above.
It is common regardless of the host computer used.

When the input / output data editing unit 27 (the input data editing unit 28 thereof) receives the dictionary search request 61 input from the data input / output device 30, as described above, the module group (transmission / reception) corresponding to the host computer 1a is transmitted. Since the execution right 42 is set for the data editing unit 22a, the text conversion unit 24a, and the command generation unit 25a), the dictionary search instruction 63 is given to the text conversion unit 24a in the module group.

When the text conversion unit 24a receives the dictionary search instruction 63 from (the input data editing unit 28 of) the input / output data editing unit 27, the common (corresponding to the host computers 1a to 1c) common to the instruction 63 is received. A dictionary search command (dictionary search common command) 64 is issued to the command generation unit 25a.

When the command generation unit 25a receives the dictionary search common command 64 from the text conversion unit 24a, the command generation unit 25a generates a dictionary search command 65 for the host computer 1a corresponding to the command 64 and edits the transmission / reception data of the host communication unit 20. It is passed to the section 22a.

When the transmission / reception data editing unit 22a receives the dictionary search command 65 for the host computer 1a from the command generation unit 25a, the command 65 is sent to the host computer 1a in the same manner as the host computer connection command 45 described above. Unique internal data is added and passed to the kernel unit 21 as transmission data 66 to the host computer 1a. Upon receiving the transmission data 66 from the transmission / reception data editing unit 22a, the kernel unit 21 transmits the same data 66 as the transmission data 67 to the host computer 1a as it is.

When the host computer 1a receives the transmission data 67 from the kernel unit 21, if the data 47 includes a dictionary retrieval command as in this example, the (dictionary retrieval system in the host computer 1a) ) Execute the dictionary search specified by the command. Then, the host computer 1a returns a response message 68 including the retrieved data, that is, the database name list data or the used data item name list data (of which data can be transmitted in one communication) to the kernel unit 21. When the kernel unit 21 receives the response message 68 returned from the host computer 1a, the received data 6
It is passed as 9 to the transmission / reception data editing unit 22a.

When the transmission / reception data editing unit 22a receives the reception data 69 from the kernel unit 21, the transmission / reception data editing unit 22a deletes internal data specific to the host computer 1a from the data 69 and passes it to the command generation unit 25a as reception data 70.

The command generation unit 25a processes from the output of the dictionary search command 65 to the reception of the reception data 69 for the command 65, which is the dictionary search common command 6 previously received from the text conversion unit 24a.
This is repeated until the series of processing for 4 is completed, that is, until all the data requested by the command 64 is received. Then, if the dictionary search common command 64 (requested common command) is completed, the command generation unit 25a passes all the corresponding received data 70 as received data 71 to the text conversion unit 24a.

The text conversion unit 24a converts the received data 71 passed from the command generation unit 25a into a format common to the multi-host database access device 2 and stores it as the received data 72 in the common data storage unit 26 and at the same time. A reception notification 73 indicating that is sent to (the screen output unit 29 of) the output data editing unit 27.

Input / output data editing unit 27 (screen output unit 2)
When receiving the reception notification 73 from the text conversion unit 24a, 9) retrieves the corresponding reception data from the common data storage unit 26 and sets the same in the screen format corresponding to the dictionary search request that the internal unit has. A screen image 74 (of a list of database names or a list of used data item names) is created and output to (the display device 32 of) the data input / output device 30 for screen display.

The above is a multi-host database access in which transmission data including a command can be sent to a target host computer without the user being aware of the type of host computer and the format of the command. The detailed operation of the device 2 has been described by taking the connection request and the dictionary search request to the host computer 1a as an example. However, when the request is made to the other host computers 1b and 1c, and when another type of request is made (database access). The same can be done when requesting, disconnecting, etc.).

[0057]

As described in detail above, according to the present invention,
Host communication means for communicating with different host computers in one device, and the data transmitted to the partner computer is converted into data that can be identified by the partner computer, and the data received from the partner computer is the data in the internal common format. The data conversion means for converting to and the input data from the input means are edited into data of a common format,
Since the received data converted by the data converting means is provided with the input / output data editing means for editing and outputting on the screen according to the screen format, the user only needs to learn how to use one device. The operation for accessing any one of the plurality of host computers or the database in the computer can be performed, and the operation can be simplified.

[Brief description of drawings]

FIG. 1 is a block configuration diagram of a system including a multi-host database access device according to an embodiment of the present invention.

FIG. 2 is a flowchart for explaining an outline of a processing procedure when a database of a host computer is accessed from the multi-host database access device of FIG.

FIG. 3 is a diagram for explaining an operation when a connection request is made from the multi-host database access device of FIG. 1 to a host computer.

FIG. 4 is a diagram for explaining an operation when a dictionary search request is made from the multi-host database access device of FIG. 1 to the host computer.

[Explanation of symbols]

1a to 1c ... Host computer, 2 ... Multi-host database access device, 20 ... Host communication unit, 21 ... Kernel unit, 22a-22c ... Send / receive data editing unit, 23 ... Data conversion unit, 24a-24c ... Text conversion unit, 25a
25c ... Command generation unit, 26 ... Common data storage unit,
27 ... Input / output data editing unit, 28 ... Input data editing unit,
29 ... Screen output unit, 30 ... Data input / output device, 31 ... Data input device, 32 ... Display device.

Claims (1)

[Claims] 1. A host communication unit for performing transmission / reception processing adapted to the host computer with each of a plurality of host computers having a unique database accessed by a unique access method, and a data input unit, Input data such as request information to be sent to one of the plurality of host computers, which is input by the data input means, is edited into data in a common format irrelevant to the other computer, and the received data is edited to output the screen. Input / output data editing means, and input data in a common format edited by the input / output data editing means are converted into data identifiable by the partner computer and output to the host communication means.
Data conversion means for converting the data in the format peculiar to the partner computer received by the host communication means into the reception data in the common format and notifying the input / output data editing means, and the plurality of hosts A multi-host database access device, characterized in that a computer or a database in the computer can be accessed from the input means by a common operation procedure irrespective of the host computer.