JP2001256247A - Data base system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform the adding work of field without reconstructing an entire data base and to perform simultaneous editing by multiple users. SOLUTION: A data base (d) in a table form usable for a user is managed while being divided for the unit of field (f), access right information for the unit of field (f) is separately managed, and the table revision and row revision of table data (a) are managed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a database system used by a plurality of users, and more particularly, to a database system suitable for adding data items, updating data, and the like.

[0002]

2. Description of the Related Art Conventionally, a table-type database is constructed using general-purpose spreadsheet software, and this database is shared and used by a plurality of users.
Database systems for updating and managing data are widely used.

In a database system of this kind, when a user updates data or adds a new field to the database, the user first accesses the database and downloads all data of the database. This is done by editing the downloaded database and re-registering the edited database.

[0004] During editing, other users cannot access the database. If simultaneous access of a plurality of users to the database is permitted, the database is simultaneously accessed by a plurality of users. Thus, for example, while the user A accesses the database and refers to the data, the user B may update the data. In this case, user A
This is because it may not be possible to know that the data has been updated, and the data may be updated without knowing that the data is not the latest data.

[0005]

However, such a conventional database system has the following problems.

That is, when editing a database, such as updating data or adding a field, all data in the database is once downloaded, and editing is performed on the downloaded database. For this reason, there is a problem that it is difficult for a user who edits a database to perform an editing operation on a large database including data unrelated to the editing.

Further, once a user accesses a database, the database is not opened to other users until the access by the user ends. That is, in the conventional database system, since a plurality of users cannot access at the same time, when one user accesses the database to update data or add a field, the other users are
Even if the user wants to update data or add a field, the user has to wait until the access of the user ends.

The present invention has been made in view of such circumstances, and a first object of the present invention is to manage a database used by a plurality of users by dividing the database in units of fields, thereby re-creating the entire database. It is an object of the present invention to provide a database system that enables a field to be added without construction.

A second object of the present invention is to manage a database in a table format on a field-by-field basis and also to manage data revisions, so that while a user is accessing data, other users can access the data. Another object of the present invention is to provide a database system capable of performing simultaneous editing by a plurality of users by recognizing that the data has been updated by another user.

[0010]

Means for Solving the Problems In order to achieve the above object, the present invention takes the following measures.

That is, according to the first aspect of the present invention, creation of a database area in which an area to which data is to be written in a table format database is defined is accepted via a user operation, and the created database area is identified by its identification number. A certain database area ID
A database area ID assigned to the database area created by the database area creating means is searched from the stored database area ID and the same database area ID assigned to the database area. If the database area ID is not stored, database area information storage means for storing database area information, which is definition information of the created database area, in association with the database area ID assigned to the database; Define the format of a field, which is an arbitrary row or column of the field, name the defined field format with its distinguished name, the field format name, and specify the database format of the database area to which this field format applies. A database format definition unit for creating field information which is information relating an area ID and a user ID defining a user who created a field format to a field format name, and storing the field information created by the database format definition unit Field information storage means and a user ID defining a user who is permitted to access the field in the field format name
If the field format name stored in the field information storage means does not have a field ID as its identification number, The field format name is given a field ID, the field format name is associated with the field ID, and the field information storage means is updated and stored in the field information storage means. If the user ID that defines the user who is permitted to access is not associated, the field format name is associated with the user ID that defines the user who is permitted to access the field, and the per-field access right information is used for each field. Updated to access right information storage And a field information ID registration means for 憶.

Therefore, in the database system according to the first aspect of the present invention, a database in a table format can be handled for each database area which is an arbitrary part of the database.

According to a second aspect of the present invention, in the database system according to the first aspect of the present invention, an input of update data of the database is received and a database area I of a database area in which the input update data is written
D, a user ID of a user who has input update data, a table ID which is an identification number of a table including a database area in which the input update data is written when the same database includes a plurality of tables, and a revision of the database area The table data information created by the data creation unit is created from the data creation unit that creates the table data information including the number in association with the input update data, and the field information stored in the field information storage unit. Field information updating means for searching field information corresponding to the database area ID and creating update data information for writing update data inputted by the data creating means based on the searched field information and table data information; , Field information When update data information storage means for storing update data information created by the update means and table field revision information including a table revision number as a table revision number and a field revision number as a field revision number are output. Table field revision storage means for updating and storing table field revision information;
The database area information corresponding to the database area ID of the database area in which the update data information created by the field information updating means is written is acquired from the database area information storage means, and the field information stored in the field-specific access right information storage means is obtained. When the user ID of the user who has input the update data is stored as the corresponding field-based access right information based on the access right information, the user ID of the user who has input the update data determines the corresponding field-based access right. Even if it is not stored as the right information, if the table revision number of the table including the database area to which the update data information is written matches the table revision number at the time of writing, the data into which the update data information is written If the table revision number of the table that contains the database area is one of the cases to be equal to or more tables revision number of the table that contains the database area,
Update determination means for outputting the update data information, receiving the update data information output by the update determination means, acquiring the database area information corresponding to the received update data information from the database area information storage means, Data updating means for updating and storing the update data information in the update data information storage means and outputting table field revision information corresponding to the update data information to the table field revision storage means.

Therefore, in the database system according to the second aspect of the present invention, only authorized users can update data.

According to a third aspect of the present invention, in the database system according to the second aspect of the present invention, the extraction system receives input of extraction information including a database area ID of a database to be extracted, a table ID, and a user ID of a user who requests extraction. Information input receiving means, and field information corresponding to the database area ID included in the extracted information input via the extracted information input receiving means are obtained from the field information storage means, and fields defined in the database to be extracted While the field information and the extracted information are output to the data updating means as field extraction conditions for extracting the data, when the database area information and the updated data information are inputted, Supported table ID and A table field information exchange means for outputting to the user table data information in which update data has been written in the database area defined by the database area ID, wherein the data update means has a field extraction condition from the table field information exchange means. When output, database area information and update data information corresponding to the field extraction condition are obtained from the database area information storage means and the update data information storage means, respectively, and output to the table field information exchange means.

Therefore, in the database system according to the third aspect of the present invention, data can be extracted only by authorized users.

[0017]

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

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

FIG. 1 is a conceptual diagram showing an example of the entire configuration of a database system according to an embodiment of the present invention.

FIG. 2 is a block diagram showing an example of the overall configuration of the database system according to the embodiment of the present invention.

As shown in FIG. 1, the database system according to the embodiment of the present invention comprises a computer such as a workstation, and is provided in a client unit 1 which is a user terminal connected to a transmission line N and a server. And a database unit 2.

Further, as shown in FIG. 2, the client unit 1 includes spreadsheet software 3 and an engineering data access unit 4.

The database unit 2 includes a database area creation unit 5, a database area information storage unit 6, a field information storage unit 7, an access right information storage unit 8 for each field, a field information ID registration unit 9, a field information Update unit 10, update data information storage unit 11, table field revision storage unit 12, update determination unit 1
3, a data update unit 14, and a table field information exchange unit 1
5 is provided.

When the database area a as shown in FIG. 3 is created, the spreadsheet software 3 inputs a creation request, as well as the database area ID of the database area a into which the input data is to be written, When the user ID and the database d are composed of a plurality of tables t, the table ID which is the identification number of the table t including the created database area a and the table data information 21 including the revision number of the database area a are input. The data is associated with the input data and output to the engineering data access unit 4 together with the input data. FIG. 4 shows a data structure diagram of the table data information 21.

The spreadsheet software 3 has a database d
The input of the format to write data to is accepted. In this case, in a database d composed of a plurality of tables t as shown in FIG. 3, the format of a field f which is an arbitrary row or column (in the example of FIG. 3, the column is defined as a field). A field format name, which is an identification name, is given to the defined format of the field f, a database area ID of the database area a to which the format of the field f is applied, and a user who defines the format of the field f are defined. It creates field information 20 which is information in which the defined user ID and a user ID defining a user who can access the database area a are associated with a field format name, and outputs the field information 20 to the engineering data access unit 4. FIG. 5 shows field information 2
0 shows a data structure diagram.

The engineering data access unit 4
It has a data display function, and displays data output from the spreadsheet software 3, the database area creation unit 5, the field information update unit 10, the update determination unit 13, and the table field information conversion unit 15.

The field information 20 output from the spreadsheet software 3 is output to the field information ID registration unit 9. Further, it outputs the table data information 21 to the database area creating unit 5 and the field information updating unit 10, respectively. When extracting desired data from the database d, the user receives input of the extraction information 22 including the database area ID and table ID of the database d to be extracted and the user ID of the user requesting the extraction, and Output to the field information converter 15. FIG. 6 shows a data structure diagram of the extraction information 22.

Further, the engineering data access unit 4 sends the data from the table field information conversion unit 15 to the database area a defined by the database area ID defined in the database area ID information 23 and the update data information 26. The written table data information 28 is obtained and output to the spreadsheet software 3.

The database area creation unit 5 outputs the table data information 21 output from the engineering data access unit 4 to the database area information storage unit 6. Further, it acquires the database area ID information 23 output from the database area information storage unit 6 and outputs it to the engineering data access unit 4.

The database area information storage section 6 acquires the table data information 21 output from the database area creation section 5. Then, the database area ID defined in the table data information 21 is searched from the already stored database area ID, and the same database area ID as the database area ID defined in the table data information 21 is not stored. In
The table data information 21 input from the database area creation unit 5 is stored in association with the database area ID. The stored database area I
The database area ID information 23, which is the list of D, is output to the database area creation unit 5, the field information ID registration unit 9, the update determination unit 13, and the data update unit 14.

The field information storage unit 7 acquires the field information 20 output from the engineering data access unit 4 via the field information ID registration unit 9 and stores the field format name as a storage name. Further, it outputs the stored field information 20 to the field information updating unit 10 and the table field information converting unit 15.

The access right information storage unit 8 for each field
Field-based access right information 2 describing accessible user IDs output from the field information ID registration unit 9
4 and outputs it to the update determination unit 13.

The field information ID registration unit 9 transmits the field information 20 from the engineering data access unit 4.
Is acquired from the database area information storage unit 6 respectively. If the field information 20 is not provided with a field ID, the field information 20 is provided with a field ID and is updated and stored in the field information storage unit 7. When the database area ID information 23 does not include the field-based access right information 24, the database area ID information 23 is associated with the field-based access right information 24 and updated and stored in the field-based access right information storage unit 8. .

The field information update unit 10 converts the field information 20 obtained from the field information storage unit 7 into a field corresponding to the database area ID included in the table data information 21 associated with the data created by the spreadsheet software 3. The information 20 is searched, and based on the searched field information 20, update data information 26 for updating the data created by the spreadsheet software 3 to a predetermined field f is created and output to the update determination unit 13. .

The update data information storage unit 11 acquires and stores the update data information 26 from the data update unit 14. The stored update data information 26 is output to the update determination unit 13.

Table field revision storage unit 12
Is the table t output by the data update unit 14.
Field revision information 2 including a table revision number which is a revision number of the table f and a field revision number which is a revision number of the field f
7 is updated and stored. Further, it outputs the table field revision information 27 to the update determination unit 13.

The update judging unit 13 receives the update data information 2 from the field information update unit 10 and the update data information storage unit 11.
6. The database area ID information 23 is obtained from the database area information storage unit 6, and the field access right information 24 is obtained from the field access right information storage unit 8. Then, first, it is determined whether the user ID of the user requesting the data update is defined in the field-specific access right information 24.

The database area a in which the data is stored is searched, and based on the update data information 26 stored in the update data information storage section 11, it is determined whether or not the data in the database area a has been changed.
The judgment result 29 is output to the engineering data access unit 4.

When there is a data change in the database area a, the update data information 26 is output to the data update unit 14 when any of the following three cases is satisfied.

(1) When the user ID included in the update data information 26 is defined as a user ID permitted to access the database area a.

(2) Even if the user ID included in the update data information 26 is not defined as a user ID permitted to access the database area a, the table revision number of the update data information 26 is When it matches the table revision number of the database area ID of area a.

(3) When the revision number of the table t of the update data information 26 is equal to or greater than the table revision number in the database area ID of the database area a.

The data update unit 14 receives the update data information 26 output from the update determination unit 13, and stores the database area ID included in the received update data information 26.
Database area ID of database ID that matches
The information 23 is acquired from the database area information storage unit 6, the received update data information 26 is stored in the update data information storage unit 11, and the table field revision information 27 of the update data information 26 is output to the table field revision storage unit 12. I do.

When the extraction information 22 is input from the table field information exchange unit 15, the data updating unit 14 transmits the database area ID information 23 corresponding to the database area ID included in the extraction information 22 to the database area information. The update data information 26 corresponding to the database area ID included in the extraction information 22 is obtained from the update data information storage unit 11 from the storage unit 6, and the update data information 26 is output to the table field information exchange unit 15.

The table field information exchange unit 15 acquires from the field information storage unit 7 the field information 20 corresponding to the database area ID and the user ID included in the extraction information 22 input via the engineering data access unit 4. The field information 20 and the extraction information 22 are output to the data updating unit 14 as field extraction conditions for extracting the field f defined in the database d to be extracted.

On the other hand, in the table field information exchange section 15, the data update section 14 sends the database area ID information 23
And the update data information 26 are input, the data is written to the database area a defined by the table ID defined by the database area ID information 23 and the update data information 26 and the database area ID. The table data information 28 is output to the engineering data access unit 4 on the requesting user side.

This network system comprises a LAN such as Ethernet (registered trademark) or a WAN to which a plurality of LANs are connected via a public line or a dedicated line. In the case of a LAN, it is composed of a number of subnets via routers as needed. In the case of a WAN, a firewall or the like for connecting to a public line is appropriately provided, but illustration and detailed description thereof are omitted here.

Next, the operation of the database system according to the present embodiment configured as described above will be described.

First, the case where the field f is created and registered will be described with reference to the flowchart of FIG.

When a new field f is added and registered in the database d in the table format, the user inputs a designation of the database area a to be created through the spreadsheet software 3 (S1). More specifically, as shown in FIG. 4, when the database d includes a plurality of tables t, the identification number of the table t including the created database area a is used. Table data information 21 including the table ID and the revision number of the database area a is created.

The table data information 21 is output from the spreadsheet software 3 to the database area creation unit 5 via the engineering data access unit 4 and further output to the database area information storage unit 6.

The database area information storage unit 6 searches the stored database area ID for the database area ID assigned to the table data information 21 (S2).

Then, the database area information storage section 6
Information already stored in the table data information 21
If the same database area ID as the database area ID does not exist (S3: Yes), the database area ID which is the definition information of the database area a
The information 23 is registered by being stored in association with the database area ID (S4).

If the same information as the database area ID of the table data information 21 exists in the information already stored in the database area information storage unit 6 (S3: No), the process returns to step S1.

On the other hand, the spreadsheet software 3 also inputs the format of the database area a to be created (S5). Specifically, as shown in FIG. 5, a field format name which is an identification name of a defined field f, a database area ID of a database area a in which data is to be written, a user ID of a user who created a format of the field f, a database When d is composed of a plurality of tables t, a table ID which is an identification number of the table t including the created database area a, and field information 2 including a user ID of a user who can access this field f
0 is created.

The field information 20 is output from the spreadsheet software 3 to the field information ID registration unit 9 via the engineering data access unit 4. If the field information 20 is not provided with a field ID, a field ID is provided based on the database area ID information 23 output from the database area information storage unit 6 and stored in the field information storage unit 7. Is registered (S6).

On the other hand, the user ID accessible from the field information 20 in the field information ID registration unit 9
The information is registered by being extracted as the per-field access right information 24 and stored in the per-field access right information storage unit 8 (S7).

The information of the database area a thus created is registered in the database area information storage section 6 together with its database ID, and the contents are reflected in the database d. The information of the field f is registered in the field information storage unit 7 together with the field ID, and the contents are reflected in the database d. Further, field-by-field access right information 24 that defines a user who can access the field f is registered in the field-by-field access right information storage unit 8, and an access right is set for each field.

That is, new fields are dynamically added to the table format database.

Next, the case of inputting and updating data to the database d will be described with reference to the flowchart of FIG.

In the case of inputting data to a predetermined database area a or updating data already described, input data and a database to which the input data is written are input by the user via the spreadsheet software 3. When the same database d includes a plurality of tables t, the database area ID of the area a includes the table ID which is the identification number of the table t including the database area a into which the input data is written, and the revision number of the database area ID. Table data information 21
Is created (S11).

The input data and table data information 21 created in step S11 are output to the field information updating unit 10. The field information updating unit 10 searches the corresponding field information 20 with reference to the database area ID of the table data information 21 created in step S11. Then, based on the retrieved field information 20, update data information 26 for updating the input data created in step S11 to a predetermined field f is created (S12) and output to the update determination unit 13. .

The update judging section 13 reads the corresponding database area ID information from the database area information storage section 6 based on the database area ID included in the update data information 26 output from the field information updating section 10. 23 are acquired (S13). Further, based on the per-field access right information 24 stored in the per-field access right information storage unit 8 and the database area ID information 23 acquired in step S13, the user is a user who is permitted access. Is determined, and the database area a to be updated is searched (S14).

Further, the update determination section 13 determines whether or not data has been changed in the database area a based on the update data information 26 created in step S12 (S15).

If there is a data change (S15:
In Yes, if any of the following conditions is satisfied, the update data information 26 is output to the data update unit 14 (S19). Otherwise (S15: No) (S1
8: No), the process returns to step S11.

(1) When the user included in the update data information 26 in the table field revision information 27 stored in the table field revision storage unit 12 is permitted to access the database area a ( S16: Yes).

(2) When this user is not permitted to access the database area a (S16: N
Even in the case of o), the table revision number of the update data information 26 matches the table revision number of the database area a (S17: Yes).

(3) When the table revision number of the update data information 26 is equal to or greater than the table revision number in the database area ID of the database a (S18: Yes).

The data update unit 14 updates the update data information 2
The database area ID information 23 of the database ID that matches the database area ID included in the database area information storage unit 6 is acquired from the database area information storage unit 6 (S2).
0). The update data information 26 is stored and registered in the update data information storage unit 11 (S21). Further, the table field revision information 27 of the update data information 26
Is output to the table field revision storage unit 12 and stored and registered (S22).

In this manner, the data created by the user who is permitted to access is registered as update data information 26 in the update data information storage unit 11 together with the database area ID, and the contents are reflected in the database area a. You. The table field revision information 27 of the update data information 26 is registered in the table field revision storage unit 12, and the contents are reflected in the database d.

That is, even if the user does not take in all the data, the data is input or updated only for the database area a where the user wants to input or update the data. Further, since it is confirmed that the revision at the time of updating the data is always the latest, even if the data is updated by another user while accessing the predetermined database area a, the data is not updated. Is recognized.

Next, a case where a desired database area a is extracted from the database d will be described with reference to the flowchart of FIG.

When a desired database area a is to be extracted from the database d, the engineering data access unit 4 inputs the database area ID and table ID of the database d to be extracted and the user of the user requesting the extraction. The extraction information 22 including the ID is created (S31) and output to the table field information conversion unit 15.

The table field information conversion section 15 obtains the field information 20 corresponding to the database area ID included in the extraction information 22 from the field information storage section 7 (S32), and stores the extraction information 22 and the field information 20 in the field information. Is output to the data updating unit 14 as a field extraction condition for extracting.

In the data update unit 14, when the field extraction condition is input from the table field information exchange unit 15, the database area ID information 23 corresponding to the database area ID included in the field extraction condition is stored in the database area information storage unit 6. (S33). Further, the update data information 26 corresponding to the database area ID included in the field extraction condition is obtained from the update data information storage unit 11 (S34).

These database area ID information 23
And the update data information 26 are the table field information exchange unit 1
5, the database area a in which the data is written is extracted based on the table ID and the database area ID defined therein (S35), and output to the requesting user side (S36).

In this way, the database area a requested by the user is extracted in the table field information exchange section 15 and output to the requesting user, so that only the required database area a is referred to.

The database area creation means, database area information storage means, database format definition means, field information storage means, field-based access right information storage means, and field information ID registration means described in claim 1 are the same as those of the above embodiment. , A database area creation unit 5, a database area information storage unit 6, a spreadsheet software 3, a field information storage unit 7, a field-based access right information storage unit 8, and a field information ID registration unit 9, respectively.

The field information updating means, the update data information storage means, the table field revision storage means, the update determination means, and the data update means according to claim 2 are:
In the above embodiment, the field information updating unit 10,
It corresponds to the update data information storage unit 11, the table field revision storage unit 12, the update determination unit 13, and the data update unit 14, respectively.

Further, the extracted information input accepting means and the table field information exchanging means in claim 3 correspond to the engineering data access unit 4 and the table field information exchanging unit 15 in the above embodiment.

As described above, in the database system according to the present embodiment, the tabular database which can be used by the user is divided into fields and managed by the above-described operation. Access rights of units can be managed individually.

That is, since the data on the field newly required by the user is registered in the same database, the field can be added without reconstructing the entire database.

Further, in addition to managing the access rights of the table format database on a field-by-field basis, by managing the data revision, while one user is accessing the data, the other user can access the data. It will also be recognized that the data has been updated.

As a result, the user can access only necessary data, so that a certain user does not occupy the entire database, and simultaneous editing by a plurality of users becomes possible.

As described above, the preferred embodiments of the present invention have been described with reference to the accompanying drawings, but the present invention is not limited to such configurations. Within the scope of the technical idea described in the claims, those skilled in the art can come up with various modified examples and modified examples, and these modified examples and modified examples are also within the technical scope of the present invention. It is understood that it belongs to.

[0086]

As described above, according to the database system of the present invention, a database used by a plurality of users is divided and managed on a field-by-field basis, so that field data can be stored without reconstructing the entire database. Can be performed.

Further, in addition to managing the tabular database on a field-by-field basis, it also manages data revisions, so that while one user is accessing data, the data is updated by another user. Since it is also recognized that the editing has been performed, simultaneous editing by a plurality of users can be performed.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram showing an example of the overall configuration of a database system according to an embodiment of the present invention.

FIG. 2 is an exemplary block diagram showing an example of the entire configuration of the database system according to the embodiment;

FIG. 3 is a schematic diagram showing an example of a database.

FIG. 4 is a data structure diagram showing an example of table data information.

FIG. 5 is a data structure diagram showing an example of field information.

FIG. 6 is a data structure diagram showing an example of extraction information.

FIG. 7 is a flowchart when creating and registering a field.

FIG. 8 is a flowchart at the time of data input / update.

FIG. 9 is a flowchart when data is extracted.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Client part, 2 ... Database part, 3 ... Spreadsheet software, 4 ... Engineering data access part, 5 ... Database area creation part, 6 ... Database area information storage part, 7 ... Field information storage part, 8 ... Each field access Rights information storage unit, 9: Field information ID registration unit, 10: Field information update unit, 11: Update data information storage unit, 12: Table field revision storage unit, 13: Update determination unit, 14: Data update unit, 15 ... Table field information conversion unit, 20: Field information, 21: Table data information, 22: Extraction information, 23: Table area ID information, 24: Access right information for each field, 26: Update data information, 27: Table field revision information, 28: Table data information 29: Judgment result

Claims (3)

[Claims] The present invention accepts, via a user operation, creation of a database area in which an area to which data is to be written in a table format database is defined.
A database area creating means for assigning a database area ID as an identification number to the created database area; and a database area ID assigned to the database area created by the database area creating means from the stored database area ID. And the database area I attached to the database area
If the same database area ID as D is not stored, database area information storage means for storing database area information, which is the definition information of the created database area, in association with the database area ID assigned to the database. And defining the format of a field which is an arbitrary row or column of a database in the form of a table, adding a field format name which is an identifier to the defined field format, and applying the format of this field to the database. Database format definition means for creating field information which is information relating a database area ID of an area and a user ID defining a user who created the field format to the field format name; Was Field information storage means for storing field information; and field-based access right information storage means for storing as field-based access right information in which the field format name is associated with a user ID defining a user permitted to access the field. If the field format name stored in the field information storage means does not have a field ID as its identification number, a field ID is added to the field format name, and the field format name is A user ID that defines a user who is allowed to access the field in the field format name stored in the field-based access right information storage means, while updating and storing the field ID in the field information storage means. If is not associated A field information ID registration unit for associating the field format name with a user ID defining a user who is permitted to access the field and updating and storing the field format name as the field access right information in the field access right information storage unit; A database system comprising: 2. The database system according to claim 1, wherein the input of the update data of the database is received, a database area ID of a database area in which the input update data is written, a user ID of a user who has input the update data, When the same database is composed of a plurality of tables, the table data including the table ID, which is the identification number of the table including the database area to which the input update data is to be written, and the revision number of the database area are input to the input database. A data creation means for creating the data in association with the updated data, and a field information stored in the field information storage means, for a database area ID included in the table data information created by the data creation means. Field information updating means for searching for field information to be created and creating update data information for writing update data input by the data creating means based on the searched field information and the table data information; and An update data information storage unit that stores update data information created by the information update unit; and a table field revision number including a table revision number that is a revision number of the table and a field revision number that is a revision number of the field is output. A table field revision storage means for updating and storing the table field revision information; and a database area in a database area in which the update data information created by the field information updating means is written. A user of the user who has acquired the database area information corresponding to the ID from the database area information storage means and entered the update data based on the field-by-field access right information stored in the field-by-field access right information storage means When the ID is stored as the corresponding field-based access right information, the update data information is stored even if the user ID of the user who input the update data is not stored as the corresponding field-based access right information. If the table revision number of the table that includes the database area in which the update data information is written matches the table revision number at the time of writing, the table revision number of the table that includes the database area in which the update data information is written is changed to the database area. If the data is equal to or greater than the table revision number of the table that includes the update data, the update determination unit that outputs the update data information; and the update data that is output by the update determination unit. Receiving the information, acquiring the database area information corresponding to the received update data information from the database area information storage means, and updating and storing the received update data information in the update data information storage means; A data updating means for outputting corresponding table field revision information to said table field revision storage means. 3. The database system according to claim 2, wherein a database area I of a database to be extracted is set.
D, an extraction information input receiving means for receiving an input of extraction information including a table ID and a user ID of a user who requests the extraction, and a database area ID included in the extraction information input via the extraction information input receiving means. The field information to be extracted is obtained from the field information storage means, and the field information and the extracted information are output to the data update means as field extraction conditions for extracting fields defined in the database to be extracted. On the other hand, when the database area information and the update data information are input, the database area defined by the table ID and the database area ID corresponding to the database area information and the update data information is stored in the database area. Table to which updated data was written A table field information exchange unit that outputs data information to a user side, wherein the data update unit, when the field extraction condition is output from the table field information exchange unit, corresponds to the field extraction condition. A database system which acquires database area information and said update data information from said database area information storage means and said update data information storage means, respectively, and outputs them to said table field information exchange means.