JPH04242841A - Data base update system - Google Patents

Abstract

PURPOSE:To present a data base update system capable of high-speed processing for a data base having an index which has a string, which is a minimum unit of data, as a constituting element. CONSTITUTION:When translating a user source program P1 to a user program P2, a compiler 1 detects a logical instruction of data base update to convert it to a data base update means call. In response to the detected logical instruction, an access module generating means 2 refers to a data base definition information area DD to generate a data base access module M as an executable update instruction. When the user program P2 is executed, a data base update means 4 updates a data base DB in accordance with the update instruction of the data base access module M in the case of the data base update means call.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a database update method.

0002

[Background Art] A column is the smallest unit of data, a record is a concatenation of multiple columns, a set of records is managed as a table, and an arbitrary number of indexes each consisting of one or more arbitrary columns are created. There is a database that can be attached.

[0003] By the way, when data is updated on a table in this type of database, the index may be affected depending on the column to which the data belongs, so in such a case, the index must also be updated at the same time. No.

Conventionally, in data update processing for this type of database, when updating a table, the definition information of the index attached to the table is searched from the database definition information area, the indexes that need to be updated are known, and the indexes that need to be updated are checked. Accordingly, index update processing was performed at the same time.

Similarly, in data loading processing into a database, when data is loaded into a table, index definition information associated with the table is searched from the database definition information area and the index is generated.

[0006]

[Problems to be Solved by the Invention] As mentioned above, in conventional database update methods, index information associated with a table is searched from the database definition information area during data update processing. This has the drawback that it takes a long time from the start to the end of the process, making it impossible to perform high-speed processing.

The present invention has been proposed in view of the above points, and its purpose is to provide a database update method that can perform high-speed processing.

[0008]

[Means for Solving the Problems] In order to achieve the above object, the present invention uses a column as the minimum unit of data, a record as a concatenation of a plurality of columns, and manages a set of records as a table. In a database where an arbitrary number of indexes each consisting of one or more columns can be added, when a user source program is translated into a user program, a logical command for database update is detected and converted into a database update method call. a compiler; and an access module creation means for creating an access module that is an executable update command by referring to a database definition information area storing definition information of tables and indexes constituting the database in response to a detected logical command; and a database update means for updating the database in accordance with an update command from the access module when the database update means is called upon execution of the user program. In addition, as another form, definition information that causes additional changes to the definition information in the database definition information area in accordance with instructions for adding and changing definition information, as well as creating and re-creating an access module related to the additionally changed table or index. A creating means and a data loading means for reading data from an input file and requesting the database updating means to add data are added.

[0009]

[Operation] In the database update method of the present invention, when the compiler translates a user source program into a user program, it detects a logical command for database update and converts it into a database update means call. In response to the logical command, the access module creation means creates an access module that is an executable update command by referring to the database definition information area that stores the definition information of tables and indexes that make up the database, and executes the user program. When a database update means is called at this time, the database update means updates the database according to an update command from the access module. In addition, the definition information creation means makes additional changes to the definition information in the database definition information area according to instructions for adding and changing definition information, and causes the access module to be created and re-created regarding the additionally changed table or index. The loading means reads data from the input file and requests the database updating means to add the data.

0010

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of the database update method of the present invention.

In FIG. 1, this embodiment has a compiler 1, access module creation means 2, definition information creation means 3, database update means 4, and data load means 5 as functional parts. Further, DB is a database, DD is a database definition information area that stores definition information of tables and indexes that constitute the database DB, and P1
is a user source program including a request to update the database DB, and P2 is an executable user program after compilation. Furthermore, M is the user source program P1
This is a database access module that is created when the user program P2 is compiled and executes update processing when the user program P2 is executed. Further, R is a definition request for adding and changing definition information in the data definition information area, and F is an input file storing data to be added to the database DB.

The operation of the above embodiment will be explained below for each main means.

The compiler 1 operates as shown in FIG.

The compiler 1 first extracts a database update instruction from the user source program P1 (step 101), and determines whether the update instruction is finished (step 102).

[0016] When the update instruction is finished (step 1
02 (YES), the process ends.

[0017] If the update instruction is not finished (step 1
02 (NO), the access module creation means 2 is called to create the corresponding database access module M (step 103).

Next, the update command in the user source program P1 is called into the database update means 4 (
Convert to (call database update means) (step 1
04), return to step 101 and repeat the same process.

FIG. 3 shows an example of an update command in the user program P1, which is an SQL-DML (Str
uctured Query Language -
Data Manipulation Language
e). For Table 1, if the value in column 2 is greater than 10, this update instruction adds 1 to the value in column 1.
It shows that adding .

When a user source program P1 including an update instruction as shown in FIG. 3 is given, the compiler 1 extracts this update instruction, calls the access module creation means 2 to create a database access module M, The update command in the source program P1 is converted into a database update means call.

The access module creation means 2 operates as shown in FIG.

[0022] The access module creation means 2 firstly
A command to update table data is output to the database access module M (step 201).

Next, the column to be updated is extracted and it is determined whether the column to be updated is the end (step 202).
.

If the column to be updated is the end (YES in step 202), the process ends.

If the column to be updated is not the end (NO in step 202), the index information in the database definition information area DD is referenced to match the column to be updated, and the index to be updated is updated by updating that column. Determine whether it exists or not (
Step 203).

If there is no index to update (step 20
3), the process returns to step 202 and the same process is repeated.

If there is an index to be updated (step 20
If YES in step 3), it is determined whether the command to update the index has already been output to the database access module M (step 204).

[0028] If the index has already been output (step 2
04), the process returns to step 202 and the same process is repeated.

[0029] If the index is not already output (step 2)
If NO in 04), a command to update the index is output to the database access module M (step 205), and the process returns to step 202 to repeat the same process.

When the access module creation means 2 is called in response to the update command shown in FIG. 3, and the definition information in the database definition information area DD is as shown in FIG.
Since updating column 1 affects only index 1, access module creation means 2 outputs a command to update index 1 to database access module M.

[0031]More specifically, the definition information of the database definition information area DD is, as shown in FIG.
D1 and index information DD2, table information D
D1 exists as many times as there are defined tables, and each stores the table name, column names and attributes of the columns that make up the table, while index information DD2 exists as many times as there are indexes defined, and each stores an index. The column names and column attributes of the columns that make up the index are stored.

[0032] Furthermore, the database access module M
has a general format as shown in FIG. 7, and a set of instruction type, instruction target, and instruction information is stored multiple times as necessary. For example, the database access module M1 in FIG. 8 is an example of a database access module created in response to the update instruction in FIG. It has become. Furthermore, the database access module M2 in FIG. 9 is a database access module for updating all columns of the table for Table 1 defined as in FIG. 1
, index 2, and index 3 are updated.

Next, the definition information creation means 3 operates as shown in FIG.

[0034] The definition information creation means 3 generates data according to a definition request R from the user when additional changes are required to the definition information of tables or indexes constituting the database DB, or when loading a large amount of data. will be activated.

The definition information creation means 3 first determines whether the request is related to a table (step 301).
.

If it is related to a table (step 30
1), information regarding the table is stored in the table information DD1 (see FIG. 6) of the database definition information area DD (step 302).

Next, all database access modules M that use that table are deleted (step 303
).

Next, the access module creation means 2 is called and the erased database access module M
A new database access module M corresponding to the above is re-created (step 304).

Next, the access module creation means 2 is called to create a database access module M that updates all columns of the table (step 305), and the process ends. Note that this database access module M is used when loading data.

If the request is not related to a table (NO in step 301), information regarding the index is stored in the index information DD2 of the database definition information area DD (step 306).

Next, all database access modules M that use that index are erased (step 30
7).

Next, the access module creation means 2 is called and the erased database access module M
A new database access module M corresponding to the database access module M is re-created (step 308), and the process ends.

The database updating means 4 operates as shown in FIG.

[0044] When the database updating means 4 is called at the time of execution of the compiled user program P2, and when the data loading means 5
Starts the operation when called from .

The database updating means 4 first retrieves the next instruction from the corresponding database access module M (step 401), and determines whether the instruction is finished (step 402).

If the instruction is finished (step 402
(YES), the process ends.

If the instruction is not finished (step 402
If NO), perform the processing (update table data, update index) according to the command (step 403), and then proceed to step 401.
Return to and repeat the same process.

The data loading means 5 operates as shown in FIG.

The data loading means 5 first reads the database access module M that updates the entire table corresponding to the table requested to be loaded (step 501).

Next, data is read from the input file F (step 502), and it is determined whether the data is finished (step 503).

[0051] If the data is finished (step 50
3), the process ends.

If the data is not finished (step 50)
3 NO), calls the database update means 4 (
In step 504), the table is updated based on the already read database access module M, and the process returns to step 502 to repeat the same process.

Through the above processing, the database DB can be updated by the user source program P1, definition information can be added and changed by the definition request R, and data can be loaded by the user's instructions. Here, when updating the database DB and loading data, it is necessary to perform processing based on the database access module M created by referring to the definition information of the database definition information area DD in advance, and to refer to the database definition information area DD at the time of execution. Since there are no errors, processing can be performed at extremely high speed.

[0054]

[Effects of the Invention] As explained above, in the database update method of the present invention, a database update request is created in advance as a database access module, and processing is performed based on this database access module when processing is executed. This eliminates the need to check the definition relationships between tables and indexes when updating the database or loading data, which has the effect of significantly speeding up processing.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram showing an embodiment of a database update method of the present invention.

FIG. 2 is a flowchart showing the processing of the compiler in FIG. 1;

FIG. 3 is a diagram showing an example of update instructions included in the user source program in FIG. 1;

FIG. 4 is a flowchart showing the processing of the access module creation means in FIG. 1;

FIG. 5 is a conceptual diagram of definition information in the database definition information area in FIG. 1;

FIG. 6 is a diagram showing an example of a specific storage format of definition information in the database definition information area in FIG. 1;

FIG. 7 is a diagram illustrating an example of a database access module in FIG. 1;

FIG. 8 is a diagram illustrating an example of a database access module in FIG. 1;

FIG. 9 is a diagram illustrating an example of a database access module in FIG. 1;

FIG. 10 is a flowchart showing the processing of the definition information creation means in FIG. 1;

FIG. 11 is a flowchart showing the processing of the database update means in FIG. 1;

FIG. 12 is a flowchart showing the processing of the data loading means in FIG. 1;

[Explanation of symbols]

1... Compiler 2... Access module creating means 3... Definition information creating means 4... Database updating means 5... Data loading means P1... User source program P2... User program M... Database access module DD... Database Definition information area DB...Database F...Input file

Claims (3)

[Claims] Claim 1: The minimum unit of data is a column, a concatenation of multiple columns is a record, a set of records is managed as a table, and an arbitrary number of indexes each consisting of one or more arbitrary columns are provided. In a database that can be added, when translating a user source program into a user program, a compiler detects a logical instruction for updating the database and converts it into a database update method call, and configures the database for the detected logical instruction. an access module creation means that refers to a database definition information area that stores definition information of tables and indexes to be updated, and creates an access module that is an executable update command; and when a database update means is called when executing a user program. A database update method comprising: a database update means for updating the database according to an update instruction from the access module. [Claim 2] Definition information creation means for making additional changes to the definition information in the database definition information area in accordance with instructions for adding and changing the definition information, and for creating and re-creating an access module related to the additionally changed table or index. 2. The database update method according to claim 1, further comprising: [Claim 3] Read data from an input file,
3. The database updating method according to claim 1, further comprising data loading means for requesting the database updating means to add data.