JP2000222430A - Virtual database management system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a virtual database management system capable of securing the permeability of table position even in the case of plural database management systems using respectively different inquiry languages. SOLUTION: This system is provided with a virtual data table 2 connected to plural database management systems A to C for managing databases DBa to DBf and allowing the definition information of respective systems A to C to correspond to the definition information of derived databases and a virtual database management means 3 for receiving derived database access syntax issued from a client Ya, retrieving a table position from the table 2 and issuing an access syntax to a database management system having the retrieved table. The means 3 is provided with a syntax conversion and generation means 3b for converting the derived database access syntax into an access syntax corresponding to a specific database management system and generating and issuing the converted access syntax.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a virtual database management system.

[0002]

2. Description of the Related Art Conventionally, a virtual data table connected to a plurality of database management systems for managing one or a plurality of databases, in which definition information of each database management system is associated with definition information of a derived database, Virtual data table management means for receiving the issued derived database access syntax, searching a table position from the virtual data table, and issuing an access syntax to a specific database management system in which the searched table is stored. There have been virtual database management systems (JP-A-4-112246, JP-A-7-98669).

[0003]

The above-mentioned conventional virtual database management system enables a user of a distributed database environment to access a desired database in a centralized manner without being conscious of the database management system in which tables are stored. This is a system for ensuring transparency of the table position.

However, the conventional virtual database management system is intended for a system in which a plurality of database management systems for managing one or a plurality of databases all use the same query language, for example, the SQL language. There is a problem that it cannot be applied to a database management system using a different query language.

An object of the present invention is to provide a virtual database management system which can ensure transparency of a table position even in a plurality of database management systems using different query languages.

[0006]

In order to achieve this object, a first characteristic configuration of the virtual database management system according to the present invention is as described in claim 1 of the claims. Connected to a plurality of database management systems that manage the database, receiving a derived data access syntax issued by the client, and a virtual data table in which the definition information of each database management system and the derived database are associated with each other, Virtual data table management means for searching a table position from the virtual data table, and issuing an access syntax to a specific database management system in which the searched table is stored, the definition information of the database management system, Query language identification information of the database management system And the identification information of a table stored in each beta base, the definition information of the derived database includes identification information of a table constituting the derived database, and the virtual data table management means includes: There is provided a syntax conversion generating means for converting and generating the derived database access syntax into an access syntax corresponding to the specific database management system based on the matching language identification information and issuing the converted syntax.

[0007] As described in claim 2 of the claims, the second characteristic configuration is, in addition to the above-mentioned characteristic configuration, common to a plurality of the databases based on the key information included in the derived database access syntax. An index database for deriving identification information serving as a key is provided, and the virtual data table management means operates the syntax conversion generation means based on identification information obtained based on the index database.

According to the first characteristic configuration, since the query language identification information of the database management system is included in the definition information of the database management system, the syntax conversion generation means performs the query language identification process. Based on the information, it becomes possible to convert and generate a derived database access syntax from a client into an access syntax using a specific query language and issue it. In other words, even with a plurality of database management systems using different query languages, it is possible to realize a virtual database management system that can ensure transparency of table positions.

According to the second feature configuration, the key information included in the derived database access syntax is converted into key information common to a plurality of databases obtained based on the index database, and the access syntax for each database management system is converted. Therefore, even if access to a plurality of databases is required, it is not only unnecessary to provide an index database for each database management system, but also an index for each such database management system is required. The key information conversion processing by the database is not required.

[0010]

According to the first characteristic configuration of the present invention, as described above, even if a plurality of database management systems use different query languages, the virtual database which can ensure the transparency of the table position can be ensured. Not only can a management system be realized, but even if the support of one of the database management systems using a certain query language is lost, only the database management system can be used for other queries. Since it is only necessary to port to one of the database management systems using the matching language, the risk can be reduced as compared with the case where the query language of all database management systems is unified.

Furthermore, a database management system using a new query language can be incorporated into an existing database management system in a very short time and at a low cost.

According to the second characteristic configuration, the turnaround time can be reduced.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG. 1, a virtual database management system 1 (also referred to as a virtual server) includes one or more databases DBa, DBb,.
f, a plurality of database management systems that manage f
C, each database management system A, B, C
Virtual data table 2 in which the definition information of the client and the definition information of the derived database are associated with each other;
b,..., Yn, receives the derived database access syntax, retrieves a table position from the virtual data table, and issues an access syntax to a specific database management system in which the retrieved table is stored. Table management means 3, a database interface unit 4 for the database management systems A, B, C, and the clients Ya, Yb,..., Y
n is provided with a user interface unit 5 for n.

More specifically, databases DBa and DB
b and DBc are a database management system A (for example, IBM) using the protocol LU6.2 and the language DL / 1.
Managed by the company's IMS) and databases DBd and DBe
Is a database management system B using the protocol TCP / IP and the language SQL (Oracle's Oracle)
And the database DBf uses the protocol TCP
/ IP and language ODBC are managed by a database management system C (DB2 / 400 of IBM Corporation), which uses different protocols or languages. However, these systems are incorporated as optimal systems for each business. ing.

The database DBa records contract information and fee management information for each customer.
“b” records owned device information for each customer, and a database DBc manages construction plan information and the like for each customer. The database DBd manages meter reading information and collection information for each customer, and the database DBe manages periodic security information. These databases are managed centrally at the headquarters. The database DBf is arranged in each service shop, and records more detailed customer management information for each customer. In each of the above-mentioned database management systems, information is uniquely managed using a management number (called a use number) for specifying a customer as a key.

In the plurality of database management systems described above, it is necessary to confirm a plurality of management data for each customer at the same time. For example, when a telephone is handled at a call center or the like serving as a contact point of a customer, management data for each customer scattered in a plurality of databases is referred to via the client Ya as a terminal, and data is input.
In such a case, the virtual database management system according to the present invention is used.

The details will be described below. To describe the virtual data table 2 in detail, as shown in FIG. 2, the definition information of the database management system includes query language identification information of the database management system, identification information of a table stored in each database, and And the definition information of the derived database includes identification information of a table constituting the derived database. For example, the identification information “DBa field f1 (field f1) of the table stored in the database of the database management system in association with“ field a ”which is the identification information of the table constituting the derived database. "
And the query language identification information “SQL”. That is, information of a certain field a of the derived database which is a database requested by the client is stored in the database DB of the database management system.
This is stored in the field f1 of “a”, and it is understood from the table data that the language used for the database is SQL. In practice, these table data are configured using Oracle's DBMS.

The virtual data table management means 3 receives a derived database access syntax issued from a client, and searches for the virtual data table. The query language identification information searched by the search means 3a. Syntax conversion generating means 3b for converting and generating the derived database access syntax into an access syntax corresponding to the specific database management system and issuing the converted syntax based on the above, and derivation for storing data from the specific database management system and delivering it to the client It is composed of a database 3c.

In the user interface section 5,
Using the protocol TCP / IP, an access syntax from a client using a remote procedure call (RPC) is transferred to the virtual data table management means 3, and further converted to obtain desired data from a higher-level specific database system. The access syntax is passed to the database interface unit 4.

The procedure will be described below with reference to the flowchart shown in FIG. An access syntax “GET DB (a)” for requesting data acquisition from the client Ya to the virtual database management system 1 (a command for requesting the data of the field a of the derived database, the language including this command is arbitrary client and virtual database The virtual data table which is a unified access language between the management systems 1 and can use an existing language system or a newly defined language system, which is the latter in this embodiment.) Management means 3
The relevant data is stored in the database D by the search means 3a.
The syntax conversion and generation unit 3b searches for the language used for the database in SQL, which is stored in the field f1 of Ba, and dynamically generates an access method acquisition program corresponding to the location of the data and the SQL. , Access syntax "GETDB
(A) ”to“ SELECT f1 FROM DBa ”
And delivers it to the database interface unit 4. When data is acquired from the corresponding higher-level database (the database DBa in this embodiment), the virtual data table management means 3 incorporates the relevant data into the derived database 3c and edits the data. The data is returned to the client Ya. Hereinafter, similarly, the client Ya
In response to a plurality of data manipulation instructions from the PC, data is acquired and delivered by a remote procedure call (RPC).

Another embodiment will be described below. By the way, in the database management system described above, a description has been given that information is uniquely managed using a management number (referred to as a use number) for specifying a customer as a key. Usually, since the management number (referred to as the use number) is not specifically recognized, the management number is searched based on a plurality of pieces of information such as a name, an address, and a telephone number, and each database is searched using the searched management number. There is a need to. Normally, it is necessary to provide an index database for searching for a management number from such information as name and address for each beta base management system, and thereby to specify the management number.

However, for example, when a plurality of databases are accessed in a series of data reading processes, when a specific operation of the management number is executed for each accessed database, the turnaround time becomes longer, and the serviceability deteriorates. In practice, this will cause major problems such as customer complaints.

Therefore, in the virtual database management system according to the present invention, identification information as a key common to a plurality of the databases is obtained from a plurality of key information such as a name, an address, and a telephone number included in the derived database access syntax.
That is, an index database (not shown) for deriving a management number is provided, and the virtual data table management means operates the syntax conversion generation means 3b based on identification information obtained based on the index database, This avoids a duplicate search operation for each of the database management systems A, B, and C, thereby shortening the turnaround time. The identification information obtained based on the index database is not limited to the customer management number.

[Brief description of the drawings]

FIG. 1 is a block diagram of a virtual database management system.

FIG. 2 is a conceptual explanatory diagram of a virtual data table.

FIG. 3 is a flowchart.

[Explanation of symbols]

Reference Signs List 1 virtual database management system 1 2 virtual data table 3 virtual data table management means A, B, C database management systems DBa, DBb,..., DBf database Ya, Yb,.

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Takeshi Tanaka 4-1-2, Hirano-cho, Chuo-ku, Osaka-shi, Osaka Inside Osaka Gas Co., Ltd. (72) Inventor Takashi Suzuki 4-chome, Hirano-cho, Chuo-ku, Osaka, Osaka 1-2-2 Inside Osaka Gas Co., Ltd. (72) Inventor Koji Okuda 4-1-2 Hiranocho, Chuo-ku, Osaka-shi, Osaka F-term inside Osaka Gas Co., Ltd. 5B075 KK03 PP30 PQ05 5B082 EA05 GC04

Claims (2)

[Claims] 1. A virtual data table which is connected to a plurality of database management systems for managing one or a plurality of databases, in which definition information of each database management system is associated with definition information of a derived database, and a virtual data table issued from a client. Virtual data table management means for receiving a derived database access syntax, searching a table position from the virtual data table, and issuing an access syntax to a specific database management system in which the searched table is stored. A database management system, wherein the definition information of the database management system includes query language identification information of the database management system and identification information of a table stored in each beta base, and definition information of the derived database. Is the The virtual data table management means converts and generates the derived database access syntax into an access syntax corresponding to the specific database management system based on the query language identification information. A virtual database management system provided with a syntax conversion generation unit for issuing a syntax conversion. 2. An index database for deriving identification information serving as a key common to a plurality of the databases from key information included in the derived database access syntax, wherein the virtual data table management unit is configured to execute the processing based on the index database. 2. The virtual database management system according to claim 1, wherein said syntax conversion generation means is operated based on the obtained identification information.