JPH0267682A - database system - Google Patents

Abstract

PURPOSE:To make it possible to access also data bases having different structure by means of the same interface by providing the title system with a reference means for table defining information and a data base access means based upon a structure type data base language (DML) obtained by analyzing and converting relational data base language (SQL). CONSTITUTION:When a data retrieval request command is inputted to an I/O part 10, a request analyzing part 8 analyzes the contents of the command to identify a data base to be retrieved. When the retrieval request is outputted to a relational data base, a relational data base access part 6 utilizes the SQL as it is to access the data base and execute data retrieval. When the retrieval request is not applied to the relational data base, a structure type data base access part 7 analyzes the SQL to obtain a table name and a retrieving condition. Then, the table name is specified and a dictionary file 5 is accessed to obtain table defining information. Consequently, the access order of records in the structure type data base 4 can be determined and data retrieval can be executed by generating the DML.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a database system, and particularly to a structural database system using SQL, which is suitable for searching data in relational databases and structural databases. Note that here, SQL is an operating language for accessing relational databases, and DML is an operating language for accessing structural databases. It is configured.

[Conventional technology]

Traditional database access processing systems, for example,
As disclosed in Japanese Patent Application Laid-Open No. 59-60661,
A search command from a processing system that displays and manipulates data is used to access only one type of database structure within the computer system.

[Problem to be solved by the invention]

The above-mentioned conventional technology does not consider accessing databases with different structures.

When accessing databases with different structures, there is a problem in that access cannot be performed using the same interface.

The present invention was made in view of the above circumstances, and its purpose is to solve the above-mentioned problems in the conventional technology and to enable access using the same interface even when accessing databases with different structures. The goal is to provide a database system that

[Means to solve the problem]

The above object of the present invention is to provide a database system having a processing system that accesses a database and a processing system that displays and manipulates data with different configurations, such as a relational database and a structural database. , storage means for table definition information that expresses the record relationships of the structural database in a table format, means for referencing the table definition information, and SQL, which is an operating language for accessing the relational database, is analyzed and this is structured. DML, an operational language for accessing type databases
This is achieved by a database system characterized by providing means for converting into DML, and means for accessing a database using the DML.

[Effect]

In the database system according to the present invention, the attributes of each item constituting the table can be obtained by the table definition information reference means in the processing system that accesses the database. Furthermore, the SQL analysis means allows the processing system that performs data display and operation to recognize the name of the table to be searched, data search conditions, etc. By issuing DML based on the information of 79, etc., it becomes possible to search for data in the structural database.

〔Example〕

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

FIG. 1 is a diagram showing the overall configuration of a database system that is an embodiment of the present invention. In the figure, 1 indicates a processing system in the host computer that accesses a database, and 2 indicates a processing system in the workstation that displays and manipulates data. Both are connected by a communication line and communicate with each other.

The processing system 1 in the host computer that accesses the database includes a relational database access section 6 that accesses the relational database 3. A structural database access unit 7 that accesses the structural database 4 and dictionary file 5. Requirement analysis section 8. Data editing department9. It is composed of an input/output section 10.

Additionally, the structural database access unit 7 analyzes SQL, which is an operating language for accessing the relay terminal database, and converts it into DML, which is an operating language for accessing the structural database. The means are realized by software.

FIG. 2 shows a table definition in which the record information in the structural database 4 and the relationship between each record are expressed in a table format that can be processed using SQL.

To define a table format, fields in each record in a parent-child relationship are combined and defined as one table.

As a result, in FIG. 2, table 1 is defined from manufacturer records and product records, table 2 is defined from product records and purchase records, and table 3 is defined from product records and sales records.

Note that the record information in the structural database, the relationship between each record, and the definition information of each table 15, 16.
17 is stored in the digital file 5,
Used when searching the database.

The operation of this embodiment configured as described above will be explained below based on the operation flowchart shown in FIG. Here, from the processing system 2 shown in FIG.

An example of processing when a data search request command including the SQL shown in FIG. 3 is received will be described. In addition, the SQ shown in Figure 3
What L means is a search request for data that satisfies "Inventory quantity 1 >IOJ" from the specific example of Table 2 shown in FIG.

The specific example in FIG. 4 shows that table 2 is created from product records 12 and purchase records 13 with product numbers 1 to 3, respectively, according to the above definition.

In the processing system 1 shown in FIG. 1, a data search request command is input through the input/output unit 10 (step 21).

The request analysis unit 8 analyzes the contents of the command input above and identifies the database to be searched (step 22). If the search request is for a relational database (step 23), the relational database access unit 6 uses SQL as is,
The database is accessed and data search is performed (step 28).

If the search request is not for a relational database (step 23), the structural database access unit 7 performs a data search using the following procedure. First, the SQL in the data search request command 1- is analyzed to obtain the table name and search conditions (step 24).

In other words, the search condition shown in Figure 3 is ``inventory quantity〉l.
Obtain "O".

Next, specify the table name above to access the dictionary nanofile 5, and define the table such as the names and attributes of the fields that make up the table, and the relationship between records (product records and purchase records in table 2). Obtain information (step 25).

As a result, the access order to record 1 in the structural database 4 is determined, and the product record is
DML is issued and data search is performed under the search condition fi>IOJ (step 26).

As a result, both records of product numbers 1 (product name is television) and 3 (product name is stereo) are retrieved from the product records. Furthermore, in order to obtain data to complete the table to be displayed, purchase records with product number 1
Or search using the condition 3 to find the purchase quantity of each product number.

As a result of the above processing, the search results for table 2 include product number 2 from the table shown at the bottom of FIG.
There are two records, product numbers 1 and 3, excluding the radio.

After the data search is completed, the data editing unit 9 edits the data and transfers the search data to the processing system 2 via the input/output unit IO (step 27). The processing system 2 displays and outputs the transferred search data.

According to this embodiment, in the processing system 2, the relational database and the structural database can be accessed only through an interface using SQL, which has the effect of making operations extremely easy.

In the above embodiment, a processing system 1 that performs database access is located in a host computer, and a processing system 2 that displays and manipulates data is located in a workstation, and both are connected by a communication line and communicate with each other. Although the present invention is not limited to this example,
The present invention is also applicable to a system in which the processing system 1 that accesses the database and the processing system 2 that displays and manipulates data are installed at the same location.

〔Effect of the invention〕

As described above, according to the present invention, a processing system that performs database access includes a means for referring to table definition information that expresses record relationships in a structural database in a table format, and database access using DML that is analyzed and converted from SQL. Since the means is provided, it is possible to realize a database system that allows access through the same interface even when accessing databases with different structures, such as a relational database and a structural database.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing the overall configuration of a database system that is an embodiment of the present invention, Fig. 2 is a diagram of a table definition that expresses record information in a structural database and the relationship between each record in a table format, and Fig. 3 4 is a diagram showing the SQL for a data search request, FIG. 4 is a diagram showing details of product records and purchase records, and a specific example of Table 2, and FIG. 5 is a flowchart of data search. 1: Processing system that accesses the database, 2: Processing system that displays and manipulates data, 3: Relational database, 4: Structural database, 5: Dictionary file, 6: Relational database access section, 7: Structural database Access section, 8: Request analysis section, 9: Data editing section, 10: Input/output section, 11-14: Record 1, 15-17: Table definition, 18: SQL
, 19: Table 2゜ Diagram Diagram Product Record

Claims (1)

[Claims] 1. In a database system that has a processing system that accesses databases with different configurations, such as a relational database and a structural database, and a processing system that performs data display and manipulation, the processing system that accesses the database has a structure-based database. A means for storing table definition information that expresses record relationships in a table format, a means for referring to the table definition information, and an operation language for accessing the relational database, SQL, is analyzed and used to access the structural database. 1. A database system comprising means for converting into DML, which is an operating language for the database, and means for accessing a database using the DML.