JPH0754479B2 - How to control a database with a data dictionary directory - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a structure change of a data dictionary in a data dictionary directory system using a structured database, and particularly to data suitable for updating the data dictionary structure. A method for updating a dictionary structure.

[Conventional technology]

In the data dictionary directory system of the structured database, the structure of the dictionary itself is defined and the physical storage area of the corresponding record is determined. The structure control information of the dictionary is set in the data set, It is called a metadirectory.

In this metadirectory, the structure of the dictionary itself and the metadirectory must match, and it is common to provide a protection function that prohibits rewriting of the metadirectory only to prevent inconsistencies between the two. Is.

Therefore, in the conventional technology, when it is necessary to change the structure of the dictionary itself, it is necessary to generate a metadirectory separately by handwriting or by using a dedicated tool similar to this, and change the generated metadirectory. Then, it was necessary to define a new dictionary structure and update the dictionary with the new structure by updating the metadirectory.

Data dictionary / directory system, Ohmsha Co., Ltd. (1986, Berkiss. W. Leonhon, Bernard K. Pragman,
Translated by Ryosuke Hotaka and translated by Mitsuaki Narita, pp. 63-76 (Data D
ictionary / Directory Systems Belkis W. Leong-Hong an
d Bernard K. Plagman 1982 by John Wiley & Sons, In
There is c), but there is no mention of a method for easily generating a metadirectory and updating the structure of the dictionary itself.

[Problems to be solved by the invention]

Conventionally, the metadirectory needs to define the dictionary structure newly by handwriting or by using a dedicated tool similar to this, and the modification work of the dictionary database structure requires modification to both the definition statement and the tool. , It wasn't easy.

An object of the present invention is to generate a directory for manipulating definition information of the structure of a database registered in the dictionary and operate the same, thereby making it possible to add and change the logical structure of the database with the same ease as the structure of the dictionary itself. To provide a dictionary structure updating method that improves the operability and maintainability of updating the dictionary structure.

[Means for solving problems]

For the above purpose, the definition information of the structure of the dictionary itself is registered in the dictionary at the same time as the definition information of the logical structure of the general database is registered, and a directory is created by referring to the dictionary that defines the structure of the dictionary itself. Do this (this is called the meta-dictionary directory), further consider the structure of the dictionary as the logical structure of the database, define the structure of the dictionary (this is called the meta-dictionary), and then refer to the meta-dictionary to generate the directory. (This is referred to as a metadirectory), which is achieved by manipulating this metadirectory to update the structure of the dictionary.

[Action]

A dictionary structure updating method of the present invention refers to a data dictionary in which definition information defining a structure of a database is described, and a definition operation program for converting and generating into a table format directory for making a database easy for a user to use. Use, to register the definition information of the structure of the dictionary itself in the dictionary, generate a directory from the dictionary in which the definition information of the structure of this dictionary itself is registered (generate a directory for meta-dictionary), and assign this to a dataset. Then, the structure of the dictionary itself is defined in the data set (meta-dictionary is generated), the directory is generated from this meta-dictionary using the definition operation program (meta-directory is generated), and this meta-directory is generated. By an operation such as changing the birds, easily to update the structure of the dictionary.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 8.

A hardware configuration for implementing the present invention is shown in FIG.
Reference numeral 1 is a processor, which performs a process of searching for necessary information. Reference numeral 2 is a definition information storage memory for storing definition information, 3 is a dictionary file storage memory for storing a dictionary, 4 is a meta dictionary file storage memory for storing a meta dictionary, 5
Is a directory file storage memory for storing a directory, 6 is a definition operation program storage memory for storing a definition operation program realizing the present invention, and 7 is
A work area for storing the retrieved information is shown.

In this system, the dictionary in the dictionary file storage memory 3 determines the structure of the entire database, and the directory in the directory file storage memory 5 is a dictionary converted into a structure that is easy for the user to use.

The present invention is directed to a structured database, the basis of which is a networked data model, and in particular a data dictionary directory system having this structure.

The network type data model is a case where there is a relation between the branched fields of the logical record in the hierarchical data structure. As a method of identifying the field in the logical record and knowing its existence, the relative position is determined. It may be done by knowing, by the indicator contained in the record, or by pointers and lists. Next, the access to register the dictionary will be described.

An example of the structure of the dictionary that determines the logical structure of the database is shown in FIG. The definition information is registered by writing the name, number, information, etc. in this dictionary. This produces a dictionary.

An example of accessing the dictionary to register definition information about the structure of the database by a definition operation program is shown.

A user of the data dictionary directory gives an operation command and definition information as exemplified below to the definition operation program.

To register definition information in the dictionary, use the ENTRY operation command, for example, and specify * ENTRY DICTIONARY <dictionary member type><definitioninformation>.

Here, the <dictionary member type> is a symbol that is specified to identify the definition unit when the definition information registration in the dictionary is divided into some definition units. Also, <definition information> is a definition source registered in the dictionary.

FIG. 8 shows an example of the directory created in the table format with reference to the dictionary. The method of creating the directory may depend on the definition operation program. For example, using the ENTRY operation command, specify * ENTRY DIRECTORY <directory member type><definition information name>.

Here, <directory member type> is an identification symbol of the directory table to be generated.

The directory generation process will be described in more detail with reference to the flowchart of FIG.

In response to a directory creation request, first search the dictionary for the dictionary member with the requested name in the dictionary (201), and store the directory creation request member information in the directory creation dictionary member table, which is the history information when creating the directory. Set (20
2). Next, based on this dictionary member, the related dictionary member required for directory generation is searched (203), and if the related dictionary member exists (204), the member information of the directory generation request is stored in the dictionary generation dictionary member table. Set. When the number of related members is processed and the related dictionary members no longer exist (204), the directory group that has already been created is searched to see if there is a directory member with the name requested to be created If not (205), store the directory generation dictionary member table in the dictionary (1908),
Further, the processing for storing the directory generation dictionary member table in the directory (1909) is performed. If there is a directory member with the name requested to be created (205), the directory creation dictionary member table stored in the directory is searched (206), and the directory creation dictionary member created in the process of 202 is searched. Check if it is the same as the contents of the table. If it is found that they are the same (207), a directory member having the same content is created by the creation request, and the directory creation process is terminated.
When the contents of the two tables are different (207), the dictionary generation dictionary member table created in the process of 202 is stored in the dictionary (208), and the same table is also stored in the directory (209).
To do.

As a result, the dictionary and the directory can have history information at the time of directory generation, and it is possible to prevent the generation of members having the same contents at the time of directory generation.

Next, the processing contents of the definition operation program when the meta-directory is generated by using the definition operation program by the same method as the method of generating the directory from the dictionary will be described with reference to the flowchart of FIG.

When the definition operation program is given a control statement at startup (101), it analyzes the control statement (102) and determines whether or not the name of the meta-dictionary is specified in the control statement (103). . If the name of the meta-dictionary is specified, the meta-dictionary is generated when the meta-directory was generated previously, so this program assigns the meta-dictionary file as the dictionary (105).

If no control statement is specified or if no meta-dictionary is specified, assign a dictionary file with this program as the dictionary (10
Four). The processing so far uses the definition operation program,
This is a task to specify a dictionary and assign it to a file in order to generate a meta dictionary from the dictionary.

Generation of meta-dictionary after file allocation will be described.

Definition information is input from the definition information storage memory 2 in units of operation commands and stored in the work area (106). If no operation command is input (107), the process ends. When an operation command is entered, it is analyzed (10
8) If it is an operation command to instruct dictionary registration (109), dictionary registration processing was performed (110).
After that, the procedure returns to the step before the operation command input (106). If it is an operation command for instructing directory generation (111), directory generation processing is performed (112).

The following is an example of a control statement.The name of the logical schema that defines the logical structure of the meta-dictionary is METADIC 01, the name of the logical schema that defines the logical structure of the dictionary is DIC 01, and the definition statement of the dictionary is When registering in the meta dictionary, describe the definition as follows.

* OPTION SCMID METADIC 01 * ENTRY DICTIONARY SCHEMA DIC RECORD RECA ITEM COMPA1 CHARACTER (8) In other words, the definition statement that defines the structure of the dictionary itself is registered in the dictionary as definition information about the structure of the general database.

The information that defines the structure of the dictionary is the information on which area of which data set the logical schema and record name are stored.

An area to be newly stored can be designated in this structure definition information. With this, it is possible to change the structure of the dictionary from the stage of registering the definition information of the dictionary structure in the dictionary. Create a directory using the structure definition information registered in the dictionary. This directory is a table type that is easy for the user to use, and this is called the meta-dictionary directory. This meta-dictionary directory is created in the same way that records are assigned to a dataset to create a general user database.
Allocate a record to the data set, write out the definition information of the dictionary structure and register it, and create a meta dictionary.

When a general directory is generated, the definition operation program is activated by inputting the definition statement shown in FIG. Further, based on this meta-dictionary, the definition operation program is used to generate a directory in the same manner as the case where the directory is generated from the above-mentioned dictionary.

In this definition operation program, a metadirectory is created by using the directory creation method for the meta dictionary instead of the dictionary. Here, the directory generated from the meta dictionary is the meta directory. The metadirectory is a table type that is easy for the user to use. Since the meta dictionary is created based on the structure definition of the dictionary and converted into the table type, the logical structure of the dictionary is defined and the corresponding This is control information that determines the physical storage area of the record.

The reason why the directory generation method is used to generate the meta-dictionary directory and the meta-directory twice is that the meta-dictionary directory is generated while referencing the dictionary, so the operation for changing / updating the meta-dictionary directory is , The directory for meta-dictionary cannot be used because the protection function for preventing the inconsistency between the structure of the dictionary and the directory in which the structure is defined and made into the table format works. Therefore, the structure of the dictionary can be updated by generating a meta-dictionary separate from the dictionary, generating a meta-directory that is a directory of this meta-dictionary, and performing an updating operation of this meta-directory.

In this embodiment, the case where the same structure as the dictionary is registered in the dictionary and processed is shown.

As the definition sentence to be specified, the same definition as the dictionary structure definition sentence shown in FIG. 3 is used, and only the database name (401) is changed. That is, another database having the same structure as the dictionary is created.

When a directory is created using the meta-dictionary, the definition operation program is started by using the definition statement in the format shown in FIG. 3 as input, and the directory is created.

As the definition statement to be specified, the control statement specifying the database name (301) used as a dictionary and the definition statement of the database are used. To generate a metadirectory, specify the dictionary database name as the schema name (302) and use the following definition statement that defines the structure of the dictionary.

FIG. 5 shows files used by the definition operation program. When a general directory is created, the definition operation program (503) is started by using the operation command and definition information (502) as input, and the metadirectory (508) is loaded from the directory data set (505) and the dictionary data set is loaded. (504) is accessed to generate a directory and stored in the directory data set (505).

When generating a meta-dictionary, store the meta-dictionary structure definition statement (507) in the dictionary data set (504), generate the meta-dictionary directory (509) based on the definition statement, and then generate the directory data set (505). ). A meta-dictionary data set (506) is allocated using this meta-dictionary directory (509). Next, when generating a metadirectory, when the definition operation program (503) is started by inputting the control statement (501), operation command, and definition information (502), the directory for the meta dictionary from the directory data set (505). (509)
Is loaded, the meta dictionary is accessed, a meta directory (508) is generated, and the meta directory (508) is stored in the directory data set (505).

In the above example, the structure of the dictionary is registered as it is in the dictionary, the metadirectory is generated, and the directory structure is updated by adding or changing the metadirectory.However, when the structure of the dictionary is defined in the dictionary, the structure is changed. It is also possible to change it, and change the dictionary structure at the stage of allocating a dataset and writing the structure definition information based on the meta-dictionary directory, that is, at the stage of generating the meta-dictionary. It is also possible to generate and update the structure of the dictionary.

According to the present invention, by using two libraries, a dictionary and a meta dictionary, a single program can easily generate a meta directory.

Once this meta-dictionary has been created, it is not necessary to re-create it each time a meta-directory is created, so that the dictionary can be tuned up easily.

〔The invention's effect〕

According to the present invention, when it becomes necessary to regenerate a metadirectory such as adding dictionary management information or changing a storage structure, metadictionary file allocation and job control statements are performed without using a special program. Change the definition operation, control the definition operation program control statement, and modify the dictionary definition statement, a metadirectory can be created with the same degree of simplicity as the operation of user-defined information, which is effective in improving operability and maintainability. .

[Brief description of drawings]

FIG. 1 is a hardware configuration diagram of an embodiment of the present invention, and FIG.
The figure shows an example of the overall processing of the definition operation program.
3 is a definition example for registering a dictionary structure definition statement in the meta dictionary and creating a meta directory, FIG. 4 is a definition example for registering a user database definition in the dictionary, and creating a directory, 5
FIG. 6 is a diagram showing a file structure used by the definition operation program, FIG. 6 is a flowchart diagram of a directory generation process, FIG. 7 is a diagram showing a dictionary, and FIG. 8 is a diagram showing directories. 1 ... Processor, 2 ... Definition information storage memory, 3 ...
Dictionary file storage memory, 4 ... Meta dictionary file storage memory, 5 ... Directory file storage memory, 6 ... Definition operation program storage memory, 7 ... Work area, 501 ... Control statement, 502 ... Definition information / operation Command, 503 ... Definition operation program, 504
...... Dictionary data set, 505 ...... Directory data set, 506 ...... Meta-dictionary data set, 507 ...... Meta-dictionary, 508 ...... Meta-directory, 509 ...... Meta-dictionary directory, 5
10 ... Dictionary.

Claims (3)

[Claims] 1. A data dictionary storing definition information defining a logical structure of a structural database, and a directory formed by converting all or part of the definition information into a table format referred to for accessing the database. A database system having a metadirectory referred to for accessing the data dictionary, writing dictionary definition information that is definition information indicating a structure of the data dictionary itself to the data dictionary, and converting the dictionary definition information. The first directory is generated, the dictionary definition information is written in one database accessed based on the generated first directory, and the dictionary definition information written in the one database Is converted to generate the metadirectory, and a method for controlling a database having a data dictionary directory. 2. The database further comprises generating means for generating the directory from the data dictionary, and the directory defining information stored in the one database is converted by the generating means. A method of controlling a database having a data dictionary directory according to claim 1. 3. A metadirectory updated by converting the dictionary definition information to generate the metadirectory, converting the dictionary definition information to obtain a table of the directory format, and making a change to the table. A method of controlling a database having a data dictionary directory according to claim 1, wherein