JPH02253451A - Data base managing system - Google Patents

Abstract

PURPOSE:To improve responsiveness at the definition operation of a file and to reduce the scale of a data base managing system by judging the necessity of the start-up of the change processing of a managing information part in the file by comparing two pieces of time information. CONSTITUTION:A data file 320 and a dictionary file 310 are formed in the same physical structure, and also, a data operation means 230 and a data file definition means to perform the generation or the structure change of the data file 320 from data which defines the logical structure, etc., of the file stored in the dictionary file 310 are provided. Also, by storing definition time information in the dictionary file 310, and generating time information in each file, and comparing them, the necessity of the generation or the structure change of the data file 320 is judged, and the data file definition means is started up at need. In such a way, the definition operation can be replaced by the data operation of definition information to define the logical structure of the file in the dictionary file 310, which remarkably reduces the scale of the data base managing system.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a database management method, and in particular, to improve responsiveness during file definition operations, reduce the number of commands, and facilitate the user interface. The present invention also relates to a database management method that makes it possible to reduce the scale of a database management system.

[Conventional technology]

Conventional database management system (rDBMSJ)
) and the database (DB) had a configuration as shown in FIG. The DB 50 by the 08MS20 in FIG. 10 consists of a dictionary file 60 and a data file 70. The dictionary file 60 stores definition information about each file in the DB 50. Further, the data file 70 stores actual data input by the user.

The data file 71 is logically divided into a management information section 72 and a data record section 73. The data record section 73 stores actual data in units of records. Further, the management information section 72 stores physical storage location information of each record, storage location information of the value of each item in each record, and the like.

The data operation section 40 of the DBMS 20 efficiently executes processing such as data storage and retrieval based on the information from the management information section 72.

In addition, the generation or structure modification of the data file 70 is
This is executed by the definition operation section 30 of the 8MS20. The definition operation unit 30 defines a data file according to the instruction regarding the definition of the data file 70 specified in the command 10, and records the result in the dictionary file 60. The definition process of the data file 71 was executed by the file management section 32 generating the data file or changing the management information section 72 and the data reorganization section 33 reorganizing the data in the data record section 73 .

As an all language for operating DB, "Database Language S Q LJ (JIS X 30
05-1987) and rWorki by ISO
ng Draft Database Language
e S Q L 2J (ISO/IECJTCl/5C
21N: 191118-4-13) is defined. The above SQL and 5QL2 include a database definition language (DDL) for describing definition operations that create or change the structure of data files, and a database definition language (DDL) that describes data operations that store and retrieve data in data files. There is a database manipulation language (DML). 10th
The definition operation unit 30 and data operation unit 40 of the DBMS shown in the figure process operations described in the DDL and DML, respectively. Therefore, traditional DBMS
It can be said that the structure is compatible with the grammar of SQL and 5QL2. Part of the operating language of SQL and 5QL2 is shown in FIG.

``Latest Database Management Technology J'' published by Nikkei McGraw-Hill, Inc. (W, H, Ins+on et al., 1987)
-5-12), pages 237 to 253, DB
As a technology using MS, a system that uses processing and data in a distributed environment is being considered. This data distributed processing system is considered to be effective as a means for distributing the location of information and integrating management, and as a means for distributing the load on processing devices. FIG. 12 shows a configuration example of a data distributed processing system. In FIG. 12, 830 is a personal computer, 840 is a workstation, 850 is a server, and 833, 843 and 853 are DBs, respectively.

[Problem to be solved by the invention]

In the DBMS according to the above-mentioned conventional technology, it was necessary to reorganize data in the file due to a change in the file definition. In general, data reorganization processing accesses all data in a file, which is complex and takes a long processing time, resulting in poor responsiveness when a user operates a DB.

Further, in the DBMS according to the prior art described above, even if the operation of accessing the DB is the same, different commands are used if the target is different. This makes it difficult for users to operate the DB.

In addition, in a data distributed processing system that is expected to become widespread in the future, each personal computer (PC) will also have a DB and a DBMS to manage it, but since the amount of memory installed in a personal computer is small, the DBMS
is required to be small in scale. However, the first
The DBMS with the structure shown in Figure 0 was large in scale.

The present invention has been made in view of the above circumstances, and its first purpose is to solve the above-mentioned problems in the conventional technology,
An object of the present invention is to provide a B management method that can improve responsiveness during file definition operations. Another object of the present invention is to provide a management method that reduces the number of commands and facilitates the user interface.A still further object of the present invention is to reduce the number of commands and simplify the user interface. The objective is to provide a B management method that makes it possible to reduce.

[Means to solve the problem]

The above object of the present invention is to provide a DBM that manages a DB that has data files that store data and dictionary files that store data that defines file logical structure, etc.
In S, the data file and the dictionary file have the same physical structure, a data manipulation means for searching and storing data in the data file and the dictionary file, and a logic of the files stored in the dictionary file. a data file definition means for generating or changing the structure of the data file from data defining the structure, etc.; and a data file definition means for generating or changing the structure of the data file from data defining the structure, etc.; By storing definition timing information to specify, storing generation timing information in each of the files to specify when the file was generated or the structure was changed, and comparing the definition timing information and the generation timing information. This is achieved by a DB management method characterized by determining the necessity of generating or changing the structure of the data file, and activating the data file definition means if necessary.

[Effect]

In the DB management system according to the present invention, by having the above-described configuration, the definition operation for creating a data file or changing the structure in a conventional DBMS can be performed by changing the logical structure of the file in the database file. This can be replaced by data manipulation of the definition information to be defined.

In addition, by configuring as described above, conventional DBMS
In the definition process, data reorganization processing and definition command analysis processing, which accounted for most of the processing, are no longer necessary.
The definition process of the DBMS consists of a process of changing the management information section in the file and a process of comparing timing information, which is a means of starting the definition process.

These eliminate the need for most of the definition processing in conventional DBMSs, resulting in a significant reduction in the scale of the DBMS.

〔Example〕

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

FIG. 2 is a configuration diagram of a DB system showing an embodiment of the present invention, in which 200 is a DBMS, 300 is a D
100 indicates an operation command.

The DBMS 200 includes a timing information comparison unit 21, which will be described later.
0. A file management section 22G and a data manipulation section 230 are provided. The files in the DB 300 consist of a dictionary file 310 that stores data that defines the logical structure of the file and a data file 320 that stores normal data. In addition, here,
A case is shown in which a file register 400 and an item register 500 are stored in the digital file 310, and an address book 600 is stored in the data file 320.

FIG. 3 shows the logical structure of each file mentioned above and the data format of each part. Figure (a) shows the structure of each file. Each file in the dictionary file 310 and data file 320 is composed of a management information section 700 and a data record section 730.

It is composed of a file management information section 710 that stores management information regarding files, and an item management information section 720 that stores management information regarding each item constituting the file.

As shown in FIG. 3(b), the file management information section 710 has an area for storing generation time information 712 that specifies the time when a file was generated or its structure was changed.

The item management information section 720 also has an area for storing item identifiers 722 that specify each item, as shown in FIG. 3(c).

The data record section 73tl is composed of a plurality of items 735, as shown in FIG. 3(d). Also, each item 7
35 is composed of one item value 7349, item value length 733, and item identifier 732.

As mentioned above, the dictionary file 310 includes a file register 4 that stores data indicating file attributes.
00, and an item register 500 that stores data indicating attributes of items.

FIG. 4 shows the file format of the file registry 400. The data record section 73G of the file registry 400 has five items as shown in FIG. It has definition time information 402 indicating when the file specified by name 401 was defined.

The item management information section 720 stores the item management terminals N421 and 422 of the above-mentioned file name 401 and definition time information 402, respectively, as shown in FIG. 4(b).

In addition, generation time information 712 of the file management information section 71G
As shown in FIG. 4(a), date information “
88101101" is stored.

FIG. 5 shows a data record section 730 of the zero item register 500 showing the file format of the item register 500.
As shown in FIG. 5(c), the six-item management information section 720 has, as one item, a belonging file name 5011 that specifies the item, an item name 502, and a data type 503 that indicates the attribute of the data stored in the item. , as shown in FIG. 5B, the above-mentioned file name 5019, item name 502, and item management information 521, 522, and 523 of the data type 503 are stored, respectively. In addition, the file management information section 71
0 generation time information 712.

As shown in Figure (a), the date information "88101" indicates the time when the one-item register 500 was created or the structure was changed.
101'' is stored.

FIG. 6 shows the file format of the address book 600, and the data record section 730 of the address book 600 has a sixth file format.
Name 601, which specifies one item as one item, as shown in Figure (Q). The 0-item management information section 720, which has an address 602 and a telephone number 603, has the above-mentioned name 601. Item management information 621, 622, and 623 for the address 602 and telephone number 503 are stored. In addition, generation time information 7 of the file management information section 710
12, as shown in FIG.
/12/14" is stored.

Note that the data record section 730 of the address book 60G shown in FIG. 6(Q) includes records with three different formats, which will be described later along with the operation.

The DBM 8200 shown in FIG.
, a file management section 220, and a data manipulation section 230 that manipulates data stored in the dictionary file 310 and data file 320 described above.

The operation of the DB system of this embodiment configured as described above will be explained below according to the processing flow shown in the operation flowchart shown in FIG.

The DBM 5200 receives the command 100 requesting a file operation in the DB 300 (step 910).

This command 100 specifies the type of operation such as adding, deleting, or updating data, a file to be operated on (hereinafter referred to as "target file"), and data to be used for the operation.

The timing information comparison unit 210 in the DBM 8200 makes a determination regarding the file definition change and starts the file management unit 220 according to the following procedure (step 920). First, file definition timing information 402 regarding the target file is read from the file registry 400 (step 92
1), Next, the file management information section 71 in the target file
0, read the generation time information 712 of the target file,
Here, if the target file has not been generated, the file management unit 220 is activated (step 922).

The file management unit 220 reads the data record, which is the definition information of the target file stored in each dictionary file, and generates the target file accordingly (step 923).Meanwhile, in step 922, the generation time of the target file is determined. When information 712 is read,
Comparing the definition timing information 402 of the target file with the generation time information 712, the result of a 0 determination is determined whether or not the definition of the target file has been changed after the generation or structure change of the target file. , If a definition change has been made to the target file after the target file is generated or the structure is changed, the file management unit 220 is activated (step 924). The section 700 is changed according to the definition information regarding the target file in the dictionary file 310 (step 925).

The data manipulation section 230 in the DBMS 200 performs data manipulation on the target file according to the following procedure (step 930). First, the data record section of the target file is specified by the manipulation command 100. performing operations such as adding, deleting or updating (step 931);
Next, the data operation unit 230 determines whether the target file is a dictionary file or a data file (step 932). As a result of the determination, if the target file is a dictionary file, the operation using the operation command 100 is This is a change in the definition information of the file specified by the data that performs the update process of the definition timing information (
step 933). In this process, the definition timing information 402 in the file registry 400 of the file whose definition has been changed by the operation command 100 is updated.

Through the above processing, the result of executing the operation command 100 is returned (step 940).

As described above, in this embodiment, the dictionary file 310 and the data file 320 shown in FIG. 2 are handled with the same physical structure, with the file structure and format shown in FIG. DB shown in the figure
A one-period information comparison section 210 and a file management section 220 are provided within the MS 200. As a result, the present embodiment has the advantage that the DBMS itself can automatically generate or change the structure of files as needed from the file definition information accumulated through data manipulation. Furthermore, by identifying the value of each item using the identifiers 722 and 732 shown in FIGS. 3(c) and 3(d), it becomes unnecessary to reorganize data in the data record section 730 due to file structure changes. There is an effect.

In the system configuration as described above, the state of each file when the address book 600 is generated and the structure is changed as the data file 320 in the DB 300 is shown in FIGS. 7 to 9, respectively (a), (b) and (C) are the state before the operation and the state after the definition operation, respectively.

Indicates the state in which data has been manipulated.

FIG. 7 shows the state of each file when an address 9600 is generated as a data file 320 in the DB 30G and a data record 631 is inserted into the generated address book 600.

In this operation, first, a data record 433, which is the file definition information of the address book 600, is inserted into the file registry 400 as an operation for generating address #600, and then,
Name 60, which is an item in address book 600, in item register 500
Data records 536 and 537, which are item definition information for addresses 602 and 1, are inserted.Next, data records 631 of the address book 600 are inserted as data operations into the address book 600.

Figure 8 shows the status of each file when an operation is performed to add a new item, telephone number 603, to the address book 600 described above. As an operation, insert data record 538, which is item definition information, of telephone number 603, which is an additional item of address book 600, into one item register 500.Next, as a data operation for address book 600, data of address book 600 is inserted. Insert record 632.

FIG. 9 shows a data record 6 in the address book 600 whose definition has been changed by deleting items from the address book 600 described above.
The state of each file is shown when an operation to insert .33 is performed.

In this operation, first, as a definition change operation of the address book 600, the data record 537, which is the item definition information of the address 602, which is a deletion item of the address book 600, is deleted from the item register 500. As a data operation, the data record 633 of the address book 600 is entered.

The definition operations for each of the above operations are data operations on the dictionary file 310 described above. Therefore, through the processing in steps 932 and 933 in FIG. At the time the operation is performed, the address @600 is not generated or the structure is changed.

According to the above embodiment, the necessity of starting the change process of the management information section in the file is determined by comparing the two timing information in step 920 of FIG. is good, this allows
Improves operability during DB operation. Furthermore, in the above embodiment, the file definition operation is replaced by the data operation of the data that defines the structure, so no command is required for the definition operation. This facilitates the user interface. Furthermore, in the above embodiment, the parts that execute data reorganization processing and definition command analysis processing, which accounted for most of the definition processing by conventional DBMSs, are no longer required in the DBMS, so the scale of the DBMS is significantly increased. It also has the effect of reducing the

Note that each of the above operations results in 1. In the data record section 730 of the address book 600, records having three different formats as shown in FIG. 6(C) coexist. However, according to the embodiment described above, it is possible to store and retrieve desired item values based on the item identifier added to each item value and the length of the item value. As a result, in the data operations shown in FIGS. 8 and 9, the definition operation is performed after the address book 600 is generated or the structure is changed, so steps 924 and 92 in FIG.
5, the structure of the address book 600 is changed, but only the file management information section 710 and item management information section 720 of the address book 600 are updated, and data reorganization of already stored data records is not performed. It won't happen.

〔Effect of the invention〕

As described in detail above, according to the present invention, responsiveness during file definition operations is improved.

This has the remarkable effect of reducing the number of commands, making the user interface easier, and realizing a database management method that makes it possible to reduce the scale of the database management system.

[Brief explanation of drawings]

Figure 1 is a flowchart showing the operation of each part in a DBMS that is an embodiment of the present invention, Figure 2 is a configuration diagram of the DB system of the embodiment, and Figure 3 is the logical configuration of each file and the data format of each part. Figures 4 to 6 show
The figure shows the detailed configuration of each file, Figures 7 to 9 are diagrams showing the file status showing the specific operation of the embodiment, Figure 1O is a configuration diagram of a system according to the prior art, and Figure 11 is FIG. 12 is a diagram showing objects and operations in SQL DDL and DML commands, and is a diagram showing an example of the configuration of a data distributed processing system. 200: DBMS, 21O: Timing information comparison section, 220:
File management section, 230: Data operation section, 300: DB
, 310: Dixie 1 file, 320: Data file, 400: File register, 402: Definition time information, 500: Item register, 600: Address book, 712: Generation time information, 732: Item identifier, 733: Item Length of value, 734: Value of item.

Claims (1)

[Claims] 1. In a database management system that manages a database having a data file that stores data and a dictionary file that stores data that defines a file logical structure, etc., the data file and the dictionary file are the same. a data manipulation means for searching and storing the data in the data file and the dictionary file, and a data manipulation means for searching and storing the data in the data file and the dictionary file; data file definition means for generating or changing the structure; further, the dictionary file stores definition time information specifying the time when data defining the logical structure of each of the files was accumulated; Each file stores generation time information that specifies the time when the file was created or the structure was changed, and by comparing the defined time information and the generation time information, the data file is generated or the structure is changed. A database management method characterized by determining necessity and activating the data file definition means if necessary. 2. Each item in each record in the file consists of an item identifier, an item value length, and an item value, and the data manipulation means refers to the item identifier and the item value length. 2. The database management method according to claim 1, wherein the value of each item is manipulated by performing the following steps.