JP2000267909A - Database system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently operate a database itself when providing a table operation interface for a network type database system by providing a database operation request processing means, etc., which performs a command generating process based on an analyzed operation request and a process for expanding execution result data into table data. SOLUTION: According to an analysis result, an operation request acceptance part 2 issues requests for the extraction of record data 51 from a database 5 and table data expansion to a database operation request processing part 3 and a request to store the expanded table data to a table operation request processing part 4. The database request processing part 3 issues a database access command for extracting the record data 51 from a database 5 at the request. Further, processing part 3 expands the record data received from the database 5 to the form of table data and passes them to the table operation request processing part 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a database system, and more particularly to a database system capable of referring to and updating a network-type database with a table operation interface.

[0002]

2. Description of the Related Art Conventionally, network-type databases have been widely used in large-scale general-purpose computers and the like. However, since a user or an application program operates data in units of codes, database references and updates must be performed in units of records. It must be described procedurally on the basis, and there are aspects that are difficult to use.

[0003] On the other hand, it is known that a relational database can provide a relatively easy-to-use interface based on data manipulation on a table basis. Therefore, a method has been considered in which a network-type database can be referenced and updated using a table operation interface similar to that of a relational database. For example, in a database system described in Japanese Patent Application Laid-Open No. 2-67682, SQL, which is an operation language of a relational database, is analyzed and converted into DML, which is an operation language of a network type database, to convert a network-type database by table operation. Operation is realized. In the database access system described in Japanese Patent Application Laid-Open No. 4-299559, a sequence of access modules indicating conditions and procedures for operating a network database is generated from a query sentence to a relational database, and the sequence is sequentially executed. Function is realized. In each case, the actual database operation is realized by providing a user interface for the table operation of the relational database and providing a means for converting the operation into the operation of the network type database.

[0004]

However, in the above-mentioned prior art, for example, after a certain data A is referred to, the next data B is referred from the data A, and the table is interactively formed. In the case of a processing mode in which updating is performed as needed while operating, each operation on the table requires a complicated record operation on the network-type database with conversion, making efficient operation difficult. There is.

An object of the present invention is to provide a database system capable of more efficiently operating the network database itself when providing a table operation interface to the network database system.

[0006]

In order to achieve the above object, the present invention provides an analyzing means for analyzing an operation request for a network type database, and a command generation process for a network type database based on the analyzed operation request. Database operation request processing means for performing expansion processing of execution result data for the command into table data, storage means for storing the table data,
A table operation request processing unit for operating the table data based on the operation request analyzed by the analysis unit, and a database access unit using a command for the generated table data are provided.

In the database operation request processing means, an arrangement of fields for each combination of a parent record and a child record between a parent record of one type and a child record of one type corresponding to the parent record in the network type database. Are combined to create a tuple, and a table is configured as a set of the tuples.

In addition, when a table is updated, a request for reflecting the update content to a record of a network type database corresponding to a tuple related to the update is made to a database operation request processing means. Features.

Further, in accordance with this, the table operation request processing means absorbs the difference between the structure of the database and the structure of the table when reflecting the update contents to the record of the network type database. In addition, the table and the database are associated by the association rule, and the table and the database are associated by the user inquiry. With the above configuration, referencing and updating by the table operation interface of the network type database are realized.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of a database system according to the present invention. The database system according to this embodiment includes an input / output device 1, an operation request receiving unit 2, a database operation request processing unit 3, a table operation request processing unit 4, a database 5, and a table data storage device 6. Further, the database 5 includes record data 51 and a database definition 52.

First, the configuration of the database 5 will be described. In the database 5, it is assumed that a network type database composed of records 21, 22, and 23 having a parent-child relationship as shown in FIG. 2 is constructed.
Note that records in the database 5 that are actually operated have a more complicated relationship, such as a parent record being a child record of another record. However, in FIG. Shows the simplest record relationship.

The contents of the record data 51 in the database 5 are as shown in FIG. However, here, attention is paid only to the contents of the customer record 21 and the order record 23 and the relationship between them, and the product record 22 (FIG. 2) is omitted. Customer records 21-1 to 21-4
Is the two fields 21 of “customer ID, customer name”
Order records 23-1 to 23-5 have four fields 231, 232, 233, and 234 of "slip ID, customer ID, product ID, and quantity". Each of the order records 23-1 to 23-5 has a link with a customer record having the same customer ID. In the example of FIG. 3, each order record 23-1 and 23-
2 have the same customer ID "T0001",
Each of the order records 23-1 and 23-2 is provided with a link indicated by an arrow. In addition, when there are a plurality of order records having the same customer ID, the records are linked in such a manner that a loop is formed by the customer records corresponding to the records. Although omitted here, a similar link structure is formed between the product record 22 and the order record 23 using the product ID 233 as a key. The database definition 52 describes the field configuration and link structure as described above.

FIG. 4 shows an example in which the database definition 52 of the database 5 shown in FIGS. 2 and 3 is described. For the name of the record and the type of parent and child, the name of the field included in the record, and the specific fields of the child record (customer ID and product ID in this case), specify the fields used for linking with the parent record. Its parent record name is defined.

Next, the overall procedure of the basic database reference processing and update processing by the table operation interface will be described with reference to the flowchart of FIG. First, the record data 51 is extracted from the database 5 which is a network type database, and is developed as table data (step 501). When a request for table data development is input through the input / output device 1, the request is passed to the operation request receiving unit 2 and analyzed. In this case, the request for expanding the table data includes information indicating a higher concept of the data to be expanded or the data itself. The operation request receiving unit 2 requests the database operation request processing unit 3 to extract the record data 51 from the database 5 and expand the table data to the database operation request processing unit 3 based on the result of the analysis. Issues a request to store the expanded table data.

The database operation request processing unit 3 issues a database access command for extracting the record data 51 to the database 5 in response to a request from the operation request reception unit 2. The database 5 receiving the command returns record data corresponding to the command to the database operation request processing unit 3. The database operation request processing unit 3 develops the record data received from the database 5 into the form of table data, and passes it to the table operation request processing unit 4. At this time, the table data is configured as a set of tuples in which the arrangement of fields of records having a parent-child relationship link is established between one type of parent record and one type of child record corresponding thereto in the network type database. .

The table operation request processing unit 4 stores the received table data in the table data storage device 6 and reports the completion of the table data development to the input / output device 1 (through the operation request receiving unit 2). The above processing procedure can be repeated to develop a plurality of table data.

Next, reference is made to the table data (step 502). When a table data reference request is input via the input / output device 1, the request is analyzed by the operation request receiving unit 2 as in the case of expanding the table data. The analyzed request is passed to the table operation request processing unit 4. The table operation request processing unit 4 performs the requested table data reference operation on the table data in the table data storage device 6, and returns the result to the input / output device 1 through the operation request reception unit 2. The above is the processing of referring to the table data.

As operations relating to table data reference, selection, projection, and combination, which are standard operations of a relational database, can be performed, and a plurality of reference requests can be sequentially input.

The request for referencing the table data affects only the table data and does not affect the database 5. Therefore, for example, even if a process of referring to tables one after another from various viewpoints in an interactive manner is performed, no operation on the database 5 is required at all. The network type database 5 is updated through updating the table data (step 503). When a table data update request is input through the input / output device 1, the request is analyzed by the operation request receiving unit 2 as in the case of referring to the table data, and is passed to the table operation request processing unit 4.

When the requested table data update is reflected in the database 5, the table operation request processing unit 4 associates the update on the table with the update on the database 5. Check if there are any obvious points and make inquiries to the user if necessary. The inquiry is made from the operation request receiving unit 2 through the input / output device 1 and reflected in the update content determination of the database 5. It updates the table data in the table data storage device 6 and issues an update request for the record data 51 of the database 5 to the database operation request processing unit 3.

The database operation request processing unit 3 issues a database access command for updating the record data 51 to the database 5 in response to the request. The database 5 receiving the command updates the record data according to the command, and reports the result to the table operation request processing unit 4 (through the database operation request processing unit 3). The table operation request processing unit 4 reports the completion of the entire update process to the input / output device 1 (through the operation request receiving unit 2). The above is the processing of updating the table and updating the database.

Record data 51 from the database 5
Extraction and expansion into table data by combining parent records and child records in database operation request processing unit 3, table data reference that does not affect database 5, update of table data in table operation request processing unit 4, and records reflecting the update The feature of the present invention is the inconsistency check at the time of updating the data 51 and the update of the record data 51 reflecting the update of the table data, and the association of the data by rules and queries.

Next, details of the processing in each processing stage will be described. FIG. 6 is a flowchart of the process of extracting the record data 51 and expanding the table data in the database operation request processing unit 3. Here, a description will be given assuming that a request to extract the record data 51 and expand the table data from the operation request receiving unit 2 is given together with the designation of the parent record, the child record, and the table name.

First, it is checked whether or not there is an unprocessed parent record to be extracted. If there is no unprocessed parent record (N in step 601), the process is terminated. On the other hand, if there is an unprocessed parent record (Y in step 601), one parent record is read (step 602), the child record linked to the parent record is checked, and if there is no unprocessed parent record, (N in step 603) Processing of next parent record (step 60
Move to 1). On the other hand, if there is an unprocessed child record (Y in step 603), one child record is read (step 604). Therefore, a tuple is created by combining the previously read parent record and the currently read child record, and the tuple is output as an element of table data having the specified table name (step 605). Processing of the next child record (step 603) Move on to

When the table data is expanded based on the combination of the customer record (parent) 21 and the order record (child) 23 shown in FIG. 3 according to the processing procedure described above, the table data shown in FIG. 71 is created. The table name is “customer-order”. The customer name in FIG.
For the customer record of “company”, a tuple combined with each of two order records (23-1, 23-2) linked to the customer record is output to the table of FIG. In the tuple creation, duplicated customer ID fields, which are keys for connection, are removed.

When information such as the record configuration of the record data 51, the field configuration of each record, and the field serving as a link key for each parent record of the child record is required, the processing is performed with reference to the database definition 52. In this flowchart, the table extraction processing is performed on the assumption that there is no tuple of only the parent record having no child record. If a tuple of only the parent record exists, NULL is set to the value of the field corresponding to the child record.
This can be handled by a method such as outputting a tuple as a value.

The substantial processing of referring to the table data is as follows.
This is performed by the table operation request processing unit 4 returning table data according to the request. The reference request is described in a general SQL language as a relational database search language. For example, with respect to the table 71 in FIG. 7, "select a tuple whose quantity field is larger than 2" is "SELECT * FROM customer-
Query with a search statement such as "Order WHERE Quantity>2". The result is returned as a table 81 as shown in FIG.

Extraction of record data and expansion into table data are limited to a combination of one parent record and one child record. However, when it is desired to refer to a combination of fields between other records, a plurality of records may be used. This can be achieved by creating tables by expansion and joining them.

FIG. 9 is a flowchart of a table update and database update process centered on the table operation request processing unit 4. The update request is also described in the SQL language search statement for the table 71. This is a general processing procedure, and details of updating, adding, and deleting tuples in the table 71 are different (details of each will be described later).

First, the table 71 whose update is requested
Identify the corresponding record and field in the record data 51 for the tuple and field (the position to be added in the case of adding a record), and the content of the update cannot be applied to the record data 51, or the result data It is checked whether there is a case where inconsistency occurs (step 901). As a result of the association and the check, if an inquiry about the contents of the update is necessary (Y in step 902), an inquiry is issued to the input / output device 1 through the operation request receiving unit 2 and the result is received (step 903). If the inquiry is unnecessary (N in step 902), the inquiry processing is omitted. Step 90
If a contradiction has occurred in the result of the check in step 1 or the result of the inquiry processing in step 903 (step 90).
At 4 the processing Y) is stopped. On the other hand, if there is no inconsistency (N in step 904), the corresponding update record and update field in the record data 51 including the result of the inquiry are determined (step 905). Then, the table data in the table storage device 6 is updated (step 906), and the record data 51 is updated through the database operation request processing unit 3 (step 907).

FIG. 10 is a detailed flowchart of the association and inconsistency check processing when updating the field value of the tuple in the table 71 in the update processing described in FIG. First, a record to be changed is set (step 1001), and a field to be changed is set therein (step 1002). At this time, if the field to be changed is not a field of the parent record (step 100)
3) N) It is determined that there is no inconsistency (step 100)
4), the processing of association and check is terminated.

On the other hand, if the field to be changed is the field of the parent record (Y in step 1003), it is checked whether the tuple corresponding to the same parent record is similarly changed (step 1005). As a result, if the values of the changed fields match (Y in step 1006), it is determined that there is no inconsistency (step 10).
04) End the association and check process. On the other hand, if the values of the changed fields do not match (N in step 1006), it is determined that a contradiction has occurred (step 1).
007) Terminate the association and check processing (as a result, the update processing ends with an error).

FIG. 11 shows "UPDATE customer-order SET customer name = 'Company E'WH" in the "customer-order" table 71 of FIG.
This shows a case where an attempt is made to update a field value with a search sentence such as ERE slip ID = 'D0002'. When rewriting the table, the customer name in the second row of the table can be rewritten as "Company E", but if the result of the rewriting is to be reflected in the record data, the contents of the table based on the same customer record (parent) will be used. The first line tuple and customer name (A
), The inconsistency occurs that the customer name of the parent record is not uniquely determined. Therefore, if an attempt is made to update with the above-described search statement, an error will occur. By the way, the search statement is "UPDATE
Customer-Order SET Customer name = 'E company' WHERE Customer ID
= “T0001” ”, both the first and second lines of the table in FIG. 11 are rewritten to the customer name“ E company ”, so that the update can be performed correctly without inconsistency.

FIG. 12 shows an example of the updating process described with reference to FIG.
FIG. 14 is a detailed flowchart of the association and inconsistency check processing when a tuple is added to the table 71. First, it is checked whether a tuple having a parent record corresponding to the tuple to be added exists (step 1201). At this time, if there is no corresponding tuple (N in step 1202), it is necessary to add a parent record, so the setting of the contents of the parent record to be added and the addition position (step 1203), and the contents of the child record to be added and the addition position The setting (step 1204) is performed. On the other hand, if there is a corresponding tuple (step 1
Y) Since the addition of the parent record is not necessary, the content of the child record to be added and the addition position are set (step 120).
Perform only 4). This completes the association process. In this embodiment, no contradiction check processing is performed when adding a tuple.

FIG. 13 shows "INSERT INTO Customer-Orders VALUES ('T000)" in the "Customer-Orders" table 71 of FIG.
2 ',' Company B ',' D0006 ',' S0002 ', 6) "when an attempt is made to add a tuple with a search sentence. In this case, the customer record (parent) corresponding to the tuple to be added
(The tuple on the third line of the content indicates that the value of the field corresponding to the customer record
D is “T0002” and the customer name is “Company B”). Therefore, when a record is added, the addition is made only to the order record (child) as shown by the shaded record 23-6 in the lower column of FIG. It is embedded in the chain of links to (parent).

On the other hand, FIG. 14 similarly shows "INSERT INTO customer-order VALUES" in the "customer-order" table 71 of FIG.
('T0005', 'Company E', 'D0006', 'S0002',
6) "shows a case where an attempt is made to add a tuple with a search sentence such as"). In this case, there is no tuple having a customer record (parent) corresponding to the tuple to be added. Therefore, the records 21-5 and 23-7 are added to both the customer record (parent) and the order record (child), and the two have a mutual link.

When adding a child record, it is necessary to perform link connection processing to a parent record other than the parent record of interest (the parent record of a tuple created by combining the child record and the field).
This is done according to the value of the field of the child record which is the key of the parent record. For example, FIG. 13 and FIG.
In the case of adding the order record (child) 23-6, 23-7 in the above, only the addition and replacement of the link to the customer record (parent) of the added order record are shown in the figure, but the product ID is actually The link to the product record (parent) is also added and replaced according to the value of the field.

FIG. 15 shows an example of the updating process described with reference to FIG.
FIG. 18 is a detailed flowchart of the association and inconsistency check processing when deleting a tuple in a table 71. First, it is checked whether or not there is another tuple having the parent record corresponding to the tuple to be deleted as a parent similarly (step 150).
1). At this time, if there is no corresponding tuple (N in step 1502), a processing method is selected for record deletion (selection contents will be described later), and a record to be deleted is set according to the result (step 1503). The processing method to be selected can be set in the table operation request processing unit 4 in advance. On the other hand, if there is a corresponding tuple (Y in step 1502), only the child record needs to be deleted, so a target child record is set (step 1504). This completes the association and inconsistency check processing.

As for the selection of the record deletion processing in step 1503, when the processing method is selected in the network type database as in the present embodiment, the following options are conceivable. (1) The parent record is immediately deleted together with the child records. (2) Only the child record is immediately deleted, and the parent record is retained. (3) Immediately stop the update process (hold both parent record and child record). (4) The user is asked about (1) to (3) to make a selection. However, as described in the description of the table data expansion processing in FIG. 6, in the present embodiment, it is assumed that there is no parent record having no child record, so that (2) is excluded from the options (simultaneously (4)). Will also be excluded from the query options). The setting of the record to be deleted is (1),
Corresponding parent record and child record are set. In the case of (3), no setting is made, and in the case of (4), setting is made in the same manner as (1) or (3) according to the query result.

FIG. 16 shows “DELETE FROM customer-order WHERE slip ID = 'in the“ customer-order ”table 71 of FIG.
D0003 'is shown in a case where an attempt is made to delete a tuple using a search sentence such as "D0003'". Note that the setting of the record deletion processing method is assumed to be "(1) immediately delete parent record together with child record". In this case, since there is no tuple having the customer record (parent) corresponding to the tuple to be deleted as a parent, the corresponding customer record (parent) 21-2 according to the assumed setting of the record deletion processing method is set.
And the order record (child) 23-3 are deleted. At the same time, the link between the two records is deleted.

On the other hand, FIG. 17 similarly shows “DELETE FROM customer-order WHERE” in the “customer-order” table 71 of FIG.
This shows a case where an attempt is made to delete a tuple using a search sentence such as “slip ID = 'D0002'”. In this case, there is a tuple having the customer record (parent) corresponding to the tuple to be deleted as a parent (the tuple on the first content line has a customer ID “T0” for the value of the field corresponding to the customer record).
001 ”, and the customer name matches“ Company A ”). Therefore, the order record (child) corresponding to the tuple to be deleted
23-8 is deleted. At the same time, the order record 23
The link from -8 is deleted and its order record 23-
The link to 8 is replaced with another record (here, the parent customer record).

When deleting a child record, it is necessary to perform a link abolition process for parent records other than the parent record of interest (the parent record of the partner who created the tuple by combining the child record and the field). This is done according to the value of the field of the child record which is the key of the parent record as in the case of addition. For example, the order record (child) 2 in FIG. 16 and FIG.
In the case of deletion of 3-3 and 23-8, only the deletion and replacement of the link to the customer record (parent) of the deleted order record are shown in the figure, but the product is actually according to the value of the product ID field. The link to the record (parent) is also deleted and replaced.

Although the table update and database update processes have been described above in the order of updating, adding, and deleting tuples on the table 71, in this embodiment, the table update is developed from the database 5 (after the table operation, the table operation is performed). Is performed only for the table 71. If you want to update the database from a table created by operating the table after expansion, it is possible only under limited conditions (such as sufficient fields to reflect in the database). In addition, inconsistency check and record association are more complicated than in the present embodiment. However, even in this case, only the contents of the condition check and the record association are added or changed, and the update processing procedure can be handled by the one shown in FIG. 9 in the present embodiment.

[0044]

As is apparent from the above description, according to the present invention, record data is extracted from a database and expanded into table data, table operations are performed on the expanded table data, and table data is updated and reflected. The update of the record data, the inconsistency check at the time of update of the record data, and the association of the data by rules and queries realize the local table reference processing and the efficient database update processing. That is, no operation of the database occurs at the time of the reference processing for the data developed as the table data. When the data on the table is referred to by various queries using the interactive format and the table is updated according to the examined result, the operation on the database is performed only when the result of the update is reflected. As a result, it is possible to provide a user with a table format operation interface,
The effect that the operation of the network type database itself can be made efficient can be obtained.

[Brief description of the drawings]

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

FIG. 2 is a diagram showing a parent-child relationship between records in a network database.

FIG. 3 is a diagram showing the contents of record data in a network database.

FIG. 4 is a diagram illustrating an example of a database definition of a network-type database.

FIG. 5 is a flowchart showing an overall procedure of basic database reference processing and update processing by a table operation interface.

FIG. 6 is a flowchart of a process of extracting record data and expanding table data in a database operation request processing unit.

FIG. 7 is a diagram illustrating an example of expanded table data.

FIG. 8 is a diagram showing an example of table data obtained by reference (selection operation for a table).

FIG. 9 is a flowchart of a table update and database update process centered on a table operation request processing unit.

FIG. 10 is a detailed flow chart of the association and inconsistency check processing when updating a field value for a tuple in a table.

FIG. 11 is a diagram illustrating an example of changes in table data and record data when an attempt is made to update a field value.

FIG. 12 is a detailed flow chart of the association and inconsistency check processing when a tuple is added to a table.

FIG. 13 is a diagram illustrating an example of changes in table data and record data when an attempt is made to add a tuple (when there is a tuple associated with the same parent record).

FIG. 14 is a diagram illustrating an example of changes in table data and record data when an attempt is made to add a tuple (when there is no tuple associated with the same parent record).

FIG. 15 is a detailed flowchart of processing for association and inconsistency check when a tuple in a table is deleted.

FIG. 16 is a diagram illustrating an example of changes in table data and record data when an attempt is made to delete a tuple (when there is no tuple associated with the same parent record).

FIG. 17 is a diagram illustrating an example of changes in table data and record data when an attempt is made to delete a tuple (when a tuple associated with the same parent record exists).

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... I / O device, 2 ... Operation request reception part, 3 ... Database operation request processing part, 4 ... Table operation request processing part, 5 ...
Database, 51: Record data, 52: Database definition, 6: Table data storage device.

Claims (4)

[Claims] 1. A database system capable of referring to and updating a network-type database by a table operation interface, analysis means for analyzing an operation request for the network-type database, and command generation processing for the network-type database based on the analyzed operation request. A database operation request processing unit for expanding the execution result data of the generated command into table data, a storage unit for storing the table data, and an operation of the table data based on the operation request analyzed by the analysis unit A database system comprising: a table operation request processing unit for performing the following; and a database access unit using a command for the generated table data. 2. The database operation request processing means,
A tuple is created by combining the arrangement of the respective fields for each combination of parent record and child record between a parent record of one type and a child record of one type corresponding to the parent record in the network type database. The database system according to claim 1, wherein the table is configured as a set. 3. The table operation request processing means sends, when a table is updated, a request for reflecting the updated contents also in a record of a network type database corresponding to a tuple related to the update, to a database operation request. 3. The database system according to claim 1, wherein the processing is performed on processing means. 4. The table operation request processing means checks the inconsistency of the database caused by record update when reflecting the update content to the record of the network database, and associates the table with the database according to the association rule. 4. The database system according to claim 3, wherein the table is associated with the database by a user inquiry.