JPH0659950A - Database system - Google Patents

Abstract

PURPOSE:To construct a database system simple in operation management. CONSTITUTION:A keyword to be retrieved and a retrieving condition are inputted from a keyword input part 12. A keyword conversion part 13 prepares a key having the same format as data stored in a data storage part 11 from the inputted keyword and retrieving condition and sends the key to a collating part 14. The collating part 14 to be a character string collating processor collates the sent key with the data stored in the data storage part 11. Information relating to the data collating result is stored in a retrieved result storing part 15 and can be displayed on a retrieved result display part 16. Since the key having the same format as the data stored in the data storage part 11 is prepared by the conversion part 13 based upon the inputted keyword and retrieving condition, the data can he directly retrieved by using the character string collating processor. Since a database is prepared by a text format, its operation management can be simplified as compared with a convensional database.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a database system, and more particularly to a database system for directly collating fixed length records by full search of text format data.

[0002]

2. Description of the Related Art Conventionally widely used database systems are roughly classified into a database using a relational data model (relational database) and a database using a network data model (network database). The relational database has a conceptual model in which each item of a record is expressed in a table format, and table reference operations and the like are performed by relational algebraic operations based on set operations. In addition, the mesh database has a conceptual model represented by a graph representation in which data is represented by nodes and the parent-child relationship is represented by directed edges. These relate to each data record that has been accumulated and the data items inside the data records, thereby attempting to perform high-speed data retrieval of a vast amount of data and centralize data management.

[0003]

In the conventional database, data management is unified by associating each data with each other, but there are some problems in use.

First, it is difficult to construct a database and manage the operation unless the relationship between each record and internal item data is sufficiently grasped. In particular, a net-type database requires knowledge of the physical data structure and access paths to the data, and is difficult to use for those who have no knowledge of the database. Further, since the database holds the relationship between data and the like, much information is required in addition to the data itself, and the scale of the database itself tends to be large compared to the actual amount of data.

In the sense of data retrieval,
A method of searching all of the accumulated data from the beginning to the end and extracting the corresponding record can be considered, but in the conventional device, the search speed is slow and not practical.

[0006]

According to the present invention, a data storage unit for storing data, a keyword input unit for inputting a keyword to be searched and a search condition, and the input keyword are suitable for the data of the data storage unit. And a keyword conversion unit for converting into a form
A collation unit that collates the generated key with the data of the data storage unit, a search result storage unit that stores the corresponding record information that matches the search condition as a result of the collation by the collation unit, and the search result In a database system including a search result display unit that presents a search result by the storage unit to a user, the collation unit is a character string collation processor, and data in the data storage unit can be directly used as a key for retrieval. It is characterized by being.

[0007]

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

FIG. 1 shows an embodiment of a database system according to the present invention.

The data storage unit 11 stores data registered as a database.

The keyword input unit 12 is a device for setting keywords to be searched by a database user and search conditions.

The keyword conversion unit 13 generates data in a format corresponding to the data format of the data storage unit 11 from the keyword or search condition input from the keyword input unit 12.

The collation unit 14 is a character string collation processor, and collates the converted keyword with the data in the data storage unit 11. This processor has the ability to collate not only one character string but a plurality of character strings at the same time. Further, the present processor obtains the end address or the start address of the matched character string as a result of the collation.

The search result storage unit 15 stores the data record information that matches the search condition as a collation result.

The search result display section 16 presents the information of the search result to the user.

Next, the operation will be described with reference to the flowchart of FIG. First, the user of this database inputs the keyword he or she wants to search from the keyword input unit 12. At this time, you can specify multiple keywords and search conditions (~
AND ~, ~ OR ~) can be specified (Step 2)
1). The keyword conversion unit 13 uses the keyword input unit 12
Based on the keyword and the search condition input from, the data that is the key at the time of matching in the matching unit 14 is generated (step 22). Since the operation of the keyword converting unit 13 and the data format of the data accumulating unit 11 are closely related to each other, the details will be described later with reference to FIGS. 3 and 4.
The data converted and generated by the keyword conversion unit 13 is sent as a search key to the collation unit 14, and the collation unit 14 collates with the data of the data storage unit 11 (step 2).
3). As a result of the collation, the information of the result data searched as the data to be extracted is stored in the search result storage unit 15 (step 24), and the search result can be displayed on the search result display unit 16 (step 25).

Next, a search method in this database system will be described. In the present database system, since the collating unit 14 uses the character string collating processor, the data is retrieved by matching the character strings by collating. Therefore, it is characterized by the conversion and generation processing of the data format of the database and the keyword data which is the search key at the time of matching.

Therefore, a case where a kind of name list having "name,""place of origin,""sex," and "date of birth" is applied to this database will be described as an example. First, the expression method of the database data stored in the data storage unit 11 will be described with reference to FIG. The record consisting of each item shown in the example can be conceptually expressed in a format as shown in FIG. 3A, but in this database, data is expressed in a text format as shown in FIG. 3B. To do. This is a fixed-length record in which a "start end code" indicating the start of the record is added to the start position of each record, and a "end code" indicating the end of the record is added to the end position.

Next, the operation of the keyword converting unit 13 for generating a key suitable for the above data format from the input keyword and search condition will be described with reference to FIG. Figure 3
It is assumed that the following search conditions and keywords are input to the text format file as shown in (B). (In this example, "?" Is a character that matches any character. Wild card).

Last name = mountain? AND Birthplace = (Chiba prefecture OR Kanagawa prefecture) Then, the keyword conversion unit generates two keys shown in Fig. 4 according to the record data format. Since the two keys generated by conversion here can be regarded as one character string, these are passed to the matching unit 14 as keys. In the character string collating processor of the collating unit, as shown in FIG.
The data in the data storage unit 13 having the text format shown in FIG. Since the processor used in this database system can collate multiple keywords and use wildcards, these keys are collated by one data search. Since the collating unit can know the start or end address of the matched character string, both the accumulated data and the key can be obtained as in the record format shown in FIG. 3B or the key format shown in FIG. If you add the start and end codes to, you can always get the address of the matching record. The obtained information is stored in the search result storage unit as shown in the flowchart of FIG.

[0020]

As described above, according to the present invention, since the collating unit uses the dedicated processor for collating the character string, the character string collation can be performed at high speed. Therefore, it is possible to directly search the character string data in the database, and it is not necessary to register the index, and the database can be easily registered and updated as a normal text file. In addition, since it does not have redundant information such as indexes and relationships between data, it is possible to store data with a smaller disk usage amount as compared with a conventional database.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a database system according to the present invention.

FIG. 2 is a flowchart for explaining the operation of the database system of FIG.

FIG. 3 is a diagram for explaining a data format of a data storage unit that constitutes the database system of FIG.

FIG. 4 is a diagram for explaining the operation of a keyword conversion unit that constitutes the database system of FIG.

[Explanation of symbols]

 11 data storage unit 12 keyword input unit 13 keyword conversion unit 14 collation unit 15 search result storage unit 16 search result display unit

Claims (3)

[Claims] 1. A data storage unit for storing data, a keyword input unit for inputting a keyword to be searched and a search condition, and a keyword conversion unit for converting the input keyword into a form suitable for the data in the data storage unit. And a collating unit that collates the key converted and generated by the keyword converting unit with the data of the data storage unit, and stores the corresponding record information that matches the search condition as a result of the collation by the collating unit. In a database system including a search result storage unit and a search result display unit that presents a search result by the search result storage unit to a user, the collation unit is a character string collation processor, and the data of the data storage unit A database system characterized in that it is possible to search using as a direct key. 2. The database system according to claim 1, wherein the data storage unit uses a text file composed of fixed-length records having a record start code and an end code as a data representation method. 3. The database system according to claim 1, wherein the keyword conversion unit generates a key having the same format as the data in the data storage unit from the input keyword and search condition and sends the key to the collation unit. .