JP2005078237A - Database device, and schema management device and method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To continuously use an existing application program even when the schema of a database is changed. <P>SOLUTION: An operation request generation part 101 of an application program execution part 10 generates a database operation request such as the reference and change of data to a database 11 based on the input of a user, and outputs the version information of an application program. An operation request(retrieval condition) and version information are supplied to a schema reconfiguration part 102, and the schema reconfiguration part 102 reconfigures the schema. An operation request issuing part 103 executes a database operation to an attribute information management table 112 of a database 10 based on the reconfigured schema. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a data structure (schema) management technique for a database device, and in particular, allows an existing application program for accessing a database device to be used as it is even if the schema is changed.

Conventionally, in order to change the data structure (schema) of a database used by a filing system, the following problems have to be solved, which has been a heavy burden on the user.
(1) Modification of a filing system-specific application program that refers to the changed schema.
(2) Stop all running application programs at the same time and replace them with the modified ones.

  It is preferable that the existing application program can be used as it is even if the schema of the database is changed.

  In Patent Document 1, the generation of a database and an application program that accesses the database is checked for eligibility, and if the eligibility is not found, the activation of the application program is stopped, and the database is destroyed by an unqualified application program. It is proposed to prevent this. In this case, there is a disadvantage that the old generation application program cannot be used.

Japanese Patent Laid-Open No. 11-238007

  The present invention has been made in consideration of the above circumstances, and even when the schema configuration in the database is changed, data is continuously updated without changing the application program that referred to the target schema. The purpose is to provide a schema management technology that can refer to and update the database.

  According to this invention, in order to achieve the above-mentioned object, the configuration as described in the claims is adopted.

  In the basic configuration example of the present invention, when a database is constructed, a part for storing actual attribute data (also referred to as an attribute information management table) and a part for managing schema information (also referred to as a schema information management table) Are created separately. The part where the schema information is managed includes, for example, attribute data attribute name, table column name, application program version information, whether update is possible, whether it is up-to-date, and version information of the application program to be connected. Schema management corresponding to. Note that the attributes reserved by the system and whose definition cannot be changed are not held in the schema information management table.

  For example, the schema is configured as follows. Since an original schema is planned for the application program, the schema configuration process may be referred to as schema reconfiguration below.

(1) First, in order to construct a schema, the following information is specified in the schema management part.
-Application program version.
-Attributes included in search conditions, and acquisition and update attribute items.
・ Purpose of using attribute data.

(2) In the schema management part, an item in which the version of the application program to be connected and the version information of the application program in the schema management part are equal is searched. At the same time, the latest item is also searched, and if the version is not the same, and the latest version does not exist in the item having the same version, it is determined as an item usable in the version of the application program.

(3) It is checked whether or not the retrieved schema information can be updated. If the purpose of use of attribute data is attribute update, the process is stopped.

(4) Check the column name information item of the retrieved schema information, and if the column name information has a value, the attribute item to be acquired and updated indicates the value of the column information on the attribute management table Configure the view as follows.

  The reference and update of the attribute data is performed as follows, for example.

(1) First, the following conditions are specified in the application program.
-Search conditions for the object you want to get or change.
・ Attribute items to be acquired or changed.

(2) The application program accesses the schema management information portion to perform schema configuration, configures a schema that conforms to the version of the application program, and acquires a view.

(3) The application program performs attribute acquisition and update operations on this view.

  Although the application program itself performs schema configuration processing, the means for processing operation requests (search conditions) sent from the application program or the database itself may perform schema configuration processing. good.

  For example, the schema of the attribute information management table is changed as follows.

(1) Specify the following conditions in the dedicated application program for schema change.
-Column name of the attribute information management table to be changed.
-Column definition after change.
-Application program version that can be used after the change.

(2) Search the schema management part and check whether the attribute definition has already been changed.

(3) If the definition of the attribute name has already been changed, a new ID that is unique in the system is acquired, and a column with the specified definition with the ID as the column name is added to the attribute table. Add its contents to the schema management table and add it as the latest definition of the same attribute name.

(4) When the definition of the attribute name is changed for the first time, the column name information of the existing attribute is made the same as the attribute name. Thereafter, the same processing as (3) is performed for all attributes.

  The present invention will be further described.

  According to this invention, in order to achieve the above-mentioned object, the configuration as described in the claims is adopted. Here, prior to describing the invention in detail, supplementary explanations of the claims will be given.

  That is, according to one aspect of the present invention, in order to achieve the above-described object, the database apparatus includes: a database body; and an operation request generation for generating an operation request for the database body in accordance with a schema planned by the application program. Means for reconfiguring the schema planned by the application program according to the version information of the application program output in relation to the operation request; and conforming to the reconfigured schema The operation request issuing means for issuing the operation request to the database main body is provided.

  In this configuration, since the schema is adaptively configured according to the version information of the application program, the database can be accessed using the existing schema as it is even when the schema of the database main body is changed.

  In this configuration, the application program execution means may constitute operation request generation means, schema reconfiguration means, and operation request issue means. The operation request processing unit such as a server device that receives an operation request from the application program execution unit or the database body itself may constitute a schema reconfiguration unit and an operation request issue unit.

  Further, the schema constructing unit has, for example, a table for determining an attribute name in the database main body actually used in relation to the operation request from the version information and the attribute name included in the operation request.

  The table preferably indicates whether the attribute value of the attribute name in the determined database can be updated by the operation request.

  In addition, the above table is updated so that the attribute name included in the operation request can be actually used in the database without being replaced with another attribute name by changing the schema of the database. It is preferable to indicate whether there is.

  The database device can be configured in various modes. For example, a database management device that manages a database, a terminal that executes a client application program that sends a database operation request, and the database operation request that is received from the terminal. The server apparatus can be configured to execute a server application program that issues a database operation request to the apparatus.

  According to another aspect of the present invention, in order to achieve the above object, the database apparatus includes: an application program executing means for executing an application program; an attribute information management table for storing attribute information; A database main body including a schema information management table for designating a column in the attribute information management table corresponding to predetermined attribute information based on a version; and the attribute information operated based on an operation request sent from the application program Column determining means for determining the columns in the management table with reference to the schema information management table in accordance with the version information of the application program sent along with the operation request; the column determined by the column determining means And it is provided an operation request execution means for executing an operation request for.

  In this configuration, even if a new column is added to the attribute information management table of the database and a new schema is prepared, the existing application program can be used as it is.

For example, the present invention is optimal for the following system, but is not limited thereto.
(1) A filing system that uses a database to manage objects that can have a hierarchical structure and are composed of images, attributes, and the like.
(2) An object managed by the database has a unique value (ID) for identifying the object in the system.
(3) The database has storage location information of entities (images and documents).

  The present invention can be realized not only as an apparatus or a system but also as a method. Of course, a part of the invention can be configured as software. Of course, software products used to cause a computer to execute such software are also included in the technical scope of the present invention.

  These and other aspects of the invention are set forth in the appended claims and will be described in detail below with reference to examples.

  According to the present invention, it is possible to refer to and update data even when the data structure (schema) of the database is changed. Thereby, it is not necessary to modify the application program in order to cope with the schema change, and the cost of application program maintenance can be reduced. Further, in a specific example, since it is possible to detect that the application program refers to and updates data in the database with the previous schema configuration, it is possible to suppress operations on application programs that do not support changes in the schema configuration. This makes it possible to prevent data destruction by the application program.

  Examples of the present invention will be described below.

  FIG. 1 schematically shows a database apparatus according to an embodiment of the present invention, FIG. 2 shows a detailed configuration example of a main part of FIG. 1, and FIG. 3 shows a data flow of the above-described embodiment. Show.

  In FIG. 1, the database device includes an application program execution unit 10, a database 11, an entity data storage unit 12, and the like.

  The application program execution unit 10 executes an application program that operates the database 11, and includes a computer and the application program executed on the computer. Functionally, the application program execution unit 10 includes an operation request generation unit 101, a schema reconfiguration unit 102, an operation request issue unit 103, an entity data operation unit 104, and the like.

  The database 11 includes a schema information management table 111, an attribute information management table 112, an entity data storage destination management table 113, and the like. When all the entity data is stored in the attribute information management table 112, the entity data storage destination management table 113 and the entity data storage unit 12 may be omitted.

  The operation request generation unit 101 of the application program execution unit 10 generates an operation request for requesting a database operation such as data reference or change to the database 11 based on a user input. Further, the operation request generation unit 101 outputs version information of the application program. The operation request (search condition) and version information are supplied to the schema reconfiguration unit 102, which reconfigures the schema. Specifically, the schema reconfiguration unit 102 reconfigures the schema with reference to the schema information management table 111 based on the version information. As shown in FIG. 2, the schema reconfiguration unit 102 can be composed of an attribute definition acquisition unit 102a and a column determination unit 102b. The attribute definition acquisition unit 102a refers to the schema information management table 111 and acquires an attribute definition for each version. The column determining unit 102b determines the operation target column (database table attribute) from the attribute definition. The schema reconfiguration will be described in detail later with reference to the flowchart of FIG.

  The operation request issuing unit 103 can be composed of an attribute information management table search unit 103a and an attribute name restoration unit 103b. The attribute information management table searching unit 103a searches the determined column. The attribute name restoration unit 103b determines an attribute name corresponding to the column based on the attribute definition for each version.

  The attribute information management table 112 is a table in which actual attribute information is stored, and is configured as shown in FIG. 5, for example. The table in the example of FIG. 5 has “ID”, “name”, “format”, “management number”, and “af0023” as attributes (columns). Among these attributes (columns), “ID”, “name”, “format”, and “management number” can be directly used as attributes of the schema by the application program, while “af0023” is the application program. It is mapped to the schema attribute of the application program by the schema information management table 111 instead of the schema attribute used for the application. Hereinafter, in order to distinguish between the attribute of the schema used for the application program and the attribute of the attribute information management table 112 of the database 11, the former is sometimes referred to as “attribute” and the latter is sometimes referred to as “column”.

  For example, among the attributes of the attribute information management table 112, “af0023” is used only as a “column”, and this “column” is converted into an “attribute” of the schema of the application program by the schema information management table 111 and used.

  The schema information management table 111 is a table that stores information (also referred to as attribute definition) used when reconfiguring a schema. Of course, the schema information management table 111 can also be used for other purposes. For example, the access authority can be limited for each version of the application program.

  The schema information management table 111 is, for example, as shown in FIG. 6. In this example, a record (“update name flag”, “column name”, “version”, “updatable flag”, “latest flag” record ( Tuple). “Attribute name” is an attribute name in the schema used by the application program. “Column name” is an attribute name (column name) in the attribute information management table 112. “Version” indicates the version of the application program to which the record is applied. The “updatable flag” indicates whether or not the attribute (column) is updatable. “Latest flag” indicates whether or not it is the latest “column” among “columns” having the same “attribute name”.

  Next, schema reconstruction and data acquisition will be described.

The schema is reconstructed as follows.
(1) First, in order to construct a schema, the following information is designated to the schema reconfiguration unit 102 (schema management part).
-Application program version.
-Attributes included in search conditions, and acquisition and update attribute items.
・ Purpose of using attribute data.

(2) The schema reconfiguration unit 102 refers to the schema information management table 111 and searches for items (records, tuples) having the same version as the version of the application program to be connected. In addition, the latest item (an item whose “latest flag” is “true”) is also searched, and the version is not equal to the version of the connected application program, and the attribute is equal to the version of the connected application program. If it does not exist, the item can be used in the version of the connected application program.

(3) Check whether the retrieved schema information is updatable. If the schema information is not updatable and the purpose of use of attribute data is attribute update, the process is stopped.

(4) Check the column name information item of the retrieved schema information, and if the column name information has a value, the attribute item to be acquired and updated indicates the value of the column information on the attribute management table Configure the view as follows.

FIG. 4 shows an example of schema reconfiguration processing. This process is as follows.
[Step S10]: An attribute included in the search condition, an attribute to be operated, and a purpose of use are designated.
[Step S11]: Whether or not an attribute definition corresponding to the version of the application program exists in the schema information management table 111 is determined for each attribute included in the search condition. If it exists, the process proceeds to step S12, and if it does not exist, the process proceeds to step S13.
[Step S12]: The corresponding attribute definition information in the schema information management table 111 is acquired. Proceed to step S14.
[Step S13]: The latest attribute definition information in the schema information management table 111 is acquired. Proceed to step S14.
[Step S14]: It is determined whether the operation is an update and an attribute definition that cannot be updated. If the determination result is yes, the process proceeds to step S15 and ends with an error. If the determination result is no, the process proceeds to step S16.
[Step S15]: Error end.
[Step S16]: It is determined whether or not the processing has been completed for all attributes of the search condition. If not completed, the process returns to step S11 to repeat the process. If completed, the process proceeds to step S17.
[Step S17]: A view is created based on the acquired attribute definition.

  This will be further described using examples of the attribute information management table 112 and the schema information management table 111 shown in FIGS. 5 and 6, respectively. In this example, when the version of the application program is “1.0”, the usable schema is “ID, name, format, management number”, and “management number” cannot be updated. On the other hand, when the version is “2.0”, “ID, name, format, af0023” can be used, and “management number” can be updated.

  A view is constructed based on this result. When the version is “2.0”, a view having “ID, name, format, management number indicating af0023” is configured, and the application program recognizes the attribute without being aware of the column name “af0023”. The information management table can be accessed. From the application program, “af0023” is identified as the “management number”.

  Next, a method for referring to and updating attribute data executed using the above-described schema reconstruction will be described.

(1) First, the following conditions are specified in the application program.
-Search conditions for the object you want to get or change.
・ Attribute items to be acquired or changed.

(2) The application program (schema reconfiguration unit 102) accesses the schema information management table 111 (schema management information part) to perform schema reconfiguration, configures a schema conforming to the version of the application program, and displays a view. get.

(3) For this view, the application program (operation request issuing unit 103) performs attribute acquisition and update operations.

  Next, a method for changing the schema of the attribute information management table 112 (database 11) will be described. By changing the schema of the database 11, the database 11 can be used with a schema planned by a new application program or the like. Of course, the database 11 can continue to be used by the previous application program by restructuring the schema described above.

(1) Specify the following conditions in the dedicated application program for schema change.
A column name of the attribute information management table 112 to be changed.
-Column definition after change.
-Application program version that can be used after the change.

(2) The schema information management table 111 (schema management part) is searched to check whether the attribute definition has already been changed.

(3) If the definition of the attribute name has already been changed, a new unique ID in the system (not limited to this, but in this example, a symbol string consisting of “af” and a 4-digit number is used. Is used, and the column of the specified definition whose ID is the column name is added to the attribute table, the contents are added to the schema management table, and the latest of the definition of the same attribute name is added.

(4) When the definition of the attribute name is changed for the first time, the column name information of the existing attribute is made the same as the attribute name. Thereafter, the same processing as (3) is performed for all attributes.

  Further description will be made using examples of the attribute information management table and the schema information management table shown in FIGS. 7 and 8, respectively. In this example, the “delivery date” attribute is newly added in version 2 of the application program so that the “management number” is not used. As is apparent from the figure, when the version of the application program is “1.0”, the usable attributes are “ID, name, format, management number”, and “management number” cannot be updated. When the version is “2.0”, “ID, name, format, delivery date” can be used, and “management number” cannot be referred to. If the application program of version “1.0” is no longer used in the system operation, the “management number” is no longer necessary as data, so the “management number” is deleted to reduce the data to be managed. Is also possible.

  As described above, according to this embodiment, even when the database schema is changed, the previous application program can be used as it is. For example, even an application program that does not support changes in the schema structure of a database used by the filing system can refer to and update data. As a result, each time the schema structure of the database is changed, the application programs can be sequentially replaced without stopping all the dedicated application programs, and the system stop time can be minimized. Therefore, the maintenance cost of the entire filing system can be reduced. In addition, when a filing system is introduced in a business backbone system, the schema structure used by the application program is checked, and connection to the database is not permitted, thereby improving security to the outside of the backbone system.

  In addition, this invention is not limited to the above-mentioned Example, A various change is possible. For example, in the above-described example, the application program execution unit 10 constitutes the operation request generation unit 101, the schema reconfiguration unit 102, and the operation request issue unit 103, and issues an operation request reconfigured to the database 11. As shown in FIG. 9, the operation request processing unit 20 receives an operation request conforming to the schema unique to the application program issued by the application program execution unit 10, and the operation request processing unit 20 performs schema reconfiguration and the like to perform reconfiguration. The configured operation request may be sent to the database 11. Further, as shown in FIG. 10, a schema reconstruction unit may be provided in the front end 114 of the database 11. Alternatively, an application program execution unit 10 may further execute an auxiliary program that intercepts an operation request output from an application program, reconfigures the schema, and sends the operation request to the database 11.

  Further, as shown in FIG. 11, the schema reconfiguration unit 102 may be configured to include an attribute definition acquisition unit 102a and an operation request conversion unit 102c. The operation request conversion unit 102c converts an operation request conforming to the schema planned by the application program into an operation request conforming to the original schema of the database, and is substantially the same as the column determination unit 102b of FIG.

  Further, as shown in FIG. 12, a database system may be constructed using a client device 100 that executes an application program, a server device 200 that executes a server application program, and a database management system 300. The client device 100 executes an application program and issues a database operation request to the server device 200. The server device 200 is, for example, a filing server, and has a schema reconfiguration function 201 and an operation request issue function 202 in addition to a filing service. The operation request issue function 202 issues an operation request to the database management system 300 using the schema reconfigured by the schema reconfiguration function 201. The database management system 300 stores and manages the schema information management table 111, the attribute information management table 112, and the entity data storage destination management table 113. The data storage device 400 stores entity data.

  In the example shown in FIG. 12, the object registration request, the object search request, and the object deletion request shown in FIGS. 13 to 15 are sent from the client device 100 to the server device 200, and based on the version information included in these requests. As in the example described above, the attribute definition is acquired, the schema is reconstructed, and the object is referenced and updated.

  In the above-described embodiment, the reconfiguration of the schema is appropriately performed using the version information of the application program. However, not only the “version” but also a schema that can be determined by the application program (schema specifying information) ) As long as it is anything. You may make it set schema specific information (predetermined identifier) at the time of application setting.

It is a figure which shows the Example of this invention typically. It is a block diagram which shows the structural example of the principal part of the said Example. It is a figure explaining the flow of data of the above-mentioned example. It is a figure explaining the example of the attribute information management table of the above-mentioned Example. It is a figure explaining the example of the schema information management table of the above-mentioned Example. It is a flowchart explaining the reconfiguration | reconstruction of the schema of the said Example. It is a figure explaining the other example of an attribute information management table in relation to the change of the schema in the above-mentioned Example. It is a figure explaining the other example of a schema information management table in relation to the change of the schema in the above-mentioned Example. It is a figure explaining the modification of the above-mentioned Example. It is a figure explaining the other modification of the above-mentioned Example. It is a figure explaining the further another modification of the above-mentioned Example. It is a figure explaining the further another modification of the above-mentioned Example. It is a figure explaining the example of the registration request | requirement used with the modification of FIG. It is a figure explaining the example of the reference request used with the modification of FIG. It is a figure explaining the example of the deletion request | requirement used by the modification of FIG.

Explanation of symbols

10 Application Program Execution Unit 11 Database 12 Entity Data Storage Unit 20 Operation Request Processing Unit 100 Client Device 101 Operation Request Generation Unit 102 Schema Reconstruction Unit 102a Attribute Definition Acquisition Unit 102b Column Determination Unit 102c Operation Request Conversion Unit 103 Issue Operation Request Unit 103a attribute information management table search unit 103b attribute name restoration unit 104 entity data operation unit 111 schema information management table 112 attribute information management table 113 entity data storage destination management table 114 front end 200 server apparatus 201 schema reconfiguration function 202 issue operation request Function 300 Database management system 400 Data storage device

Claims (19)

The database itself,
An operation request generating means for generating an operation request for the database main body in accordance with a schema planned by the application program;
Schema reconfiguring means for appropriately reconfiguring the schema planned by the application program according to the version information of the application program output in association with the operation request;
An operation request issuing means for issuing the operation request to the database main body in accordance with a reconfigured schema. The database itself,
An operation request generating means for generating an operation request for the database main body in accordance with a schema planned by the application program;
Schema reconfiguring means for appropriately reconfiguring the schema planned by the application program according to the schema specifying information output in association with the operation request;
An operation request issuing means for issuing the operation request to the database main body in accordance with a reconfigured schema.   The database apparatus according to claim 1, further comprising an application program execution unit, wherein the application program execution unit constitutes the operation request generation unit, the schema reconfiguration unit, and the operation request issue unit.   An application program execution unit; and an operation request processing unit. The application program execution unit constitutes the operation request generation unit. The operation request processing unit includes the schema reconfiguration unit and the operation request issue unit. The database apparatus according to claim 1, which is configured. The database apparatus according to claim 1, further comprising an application program execution unit, constituting the operation request generation unit, and the database main body constituting the schema reconfiguration unit and the operation request issuing unit. The database itself,
Execution means for executing an application program that generates an operation request for the database main body in accordance with a schema planned by the application program;
Schema reconfiguring means for appropriately reconfiguring a schema planned by the application program according to version information of the application program output in association with the operation request from the application program;
A database apparatus comprising: means for issuing the operation request to the database main body in accordance with a reconfigured schema.   7. The database apparatus according to claim 6, wherein the schema reconfiguring means includes a table for determining an attribute name in the database main body that is actually used in relation to the operation request from the version information and the attribute name included in the operation request. .   8. The database apparatus according to claim 7, wherein the table indicates whether or not the attribute value of the attribute name in the determined database can be updated by the operation request.   Whether the attribute name included in the operation request is up-to-date without being replaced by another attribute name in the database so that the attribute name included in the operation request is actually used in the database without being replaced by another attribute due to a change in the schema of the database. 9. The database apparatus according to claim 7 or 8, which instructs whether or not. A database management device for managing the database;
A terminal that executes a client application program that sends a database operation request;
A server device that executes the server application program that receives the database operation request from the terminal and issues the database operation request to the database device;
The server device is
Schema restructuring means configured to adaptively configure the schema of the database body applied to the operation request sent from the application program according to the version information of the application program sent along with the operation request;
A database system comprising: means for issuing the operation request to the database management device in conformity with the configured schema.   The database system according to claim 10, wherein the server device provides a filing service. In a server device that issues an operation request received from a terminal that executes a client application program to a database management device that manages a database,
Schema restructuring means configured to adaptively configure the schema of the database body applied to the operation request sent from the application program according to the version information of the application program sent along with the operation request;
And a means for issuing the operation request to the database management apparatus in conformity with the configured schema. An operation request receiving means for receiving an operation request sent from an execution means for executing an application program together with version information of the application program;
A schema restructuring unit configured to adaptively configure the schema of the database body applied to the operation request sent from the application program according to the version information of the application program sent along with the operation request;
An operation executing means for executing the operation request for the database main body in conformity with the configured schema. An operation request receiving means for receiving an operation request sent from an execution means for executing an application program together with version information of the application program;
A step in which the schema reconfiguring means adaptively configures the schema of the database body applied to the operation request sent from the application program according to the version information of the application program sent along with the operation request. When,
A database schema management method, comprising: an operation execution unit that executes the operation request on the database main body based on the configured schema. An operation request receiving step for receiving an operation request sent from the execution means for executing the application program together with the version information of the application program;
A schema restructuring step for appropriately configuring the database body schema applied to the operation request sent from the application program according to the version information of the application program sent along with the operation request;
A computer program for database schema management, which is used for causing a computer to execute an operation execution step of executing the operation request on the database main body in accordance with the configured schema. A database body constructed according to the first schema;
Execution means for executing an application program for generating an operation request conforming to the second schema for the database body;
Conversion means for converting the operation request conforming to the second schema to an operation request conforming to the first schema based on version information of the application program output in association with the operation request;
A database device comprising means for issuing a converted operation request to the database main body.   17. The database apparatus according to claim 16, wherein the conversion means includes a table for determining the attribute name of the first schema from the version information and the attribute name of the second schema.   18. The database device according to claim 17, wherein the table indicates whether or not an attribute value of the determined attribute name of the first schema can be updated by the operation request. Application program execution means for executing the application program;
A database main body including an attribute information management table for storing attribute information, and a schema information management table for designating a column in the attribute information management table corresponding to predetermined attribute information based on a version of the application program;
The column in the attribute information management table operated by the operation request generated by the application program is determined with reference to the schema information management table according to the version information of the application program output in association with the operation request. Column determining means to perform,
And a means for issuing an operation request for the column determined by the column determination means.

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