JPH01180651A - Commit synchronization control system for report file output - Google Patents

Abstract

PURPOSE:To improve the productivity of a program by making a print record invalid and establishing the rest point of a report file when a commit instruction or a rollback instruction is executed to a data base file. CONSTITUTION:The title system is provided with a report commit control means to execute the real output of the print record to a report file 13 and to establish the rest point of the report file 13 at the time of executing a commit instruction 2, report rollback control means 9 to make invalid the output of the print record after the rest point just before the report file 13 and to establish the rest point of the report file 13 at the time of executing a rollback instruction 4, a report commit control calling means 3 from a program 1 and a report rollback control calling means 5. Thus, since a conflict is not generated even when the output to the report file 13 is executed in the program 1 regardless of a commit request time or a roll back request time to a data base file 12, the productivity of the program is greatly improved.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a commit synchronization control method for outputting a report file, and particularly to a report when a program that processes a database file outputs print records to a report file. Concerning commit synchronization control method for file output.

[Conventional technology]

When updating records on a database file or adding records to a database file, after all input/output of records processed in one transaction is completed, the records updated or added to the database file are If actual output is not performed, inconsistencies may occur in data updates. For this reason, database systems employ a commitment control method that manages locking of records in database files.

Additionally, in database systems, when updating or adding records, the updated or added records are generally written out to a journal file and then
A system is used in which records in a database file are updated all at once when all record input/output processed by a transaction is completed. Then, in order to perform a batch update of the database file, a commit instruction is executed to perform the actual update of the database file, release all record locks, and establish a quiesce point for the database file, as well as a commit command that updates the database file after the previous quiesce point. Language processing programs such as COBOL and RPC are provided with a rollback instruction that invalidates an update request to the database file and returns the state of the database file to the previous quiescent point.

However, in conventional database systems, there is no means to output print records all at once or to invalidate print records once they have been output for report files, and requests for output of print records from within the program are not provided. When there was, the actual print record was immediately output to the report file. Therefore, even if a rollback instruction is executed to invalidate an update request to the database file, the contents of the report file will not be returned to the state of the previous quiescent point, and there will be an inconsistency between the contents of the report file and the contents of the database file. It was supposed to happen.

For this reason, in conventional database systems, print records that are requested to be output between commit commands are temporarily saved in the program, and print records saved after the commit command is successful are stored in a report file.
Methods have been adopted, such as a method of outputting data in bulk, and a method of separating database file update processing and report file output processing on the program.

[Problem to be solved by the invention]

In the conventional database system described above, commit commands and rollback commands guarantee synchronous updates to database files, but to report files, it is not possible to output print records all at once or invalidate print records once they have been output. Therefore, programmers must take care in programming to avoid updating the database file and outputting to the report file at the same time between commit instructions, which reduces program productivity. There is a drawback that this is one of the causes.

Additionally, if the database system goes down while the program is running, the database file can guarantee the contents as of the execution of the most recent commit command, but the report file will lose all print records from the time the program started running. , there is a drawback that there is a discrepancy between the contents of the database file and the contents of the report file.

In view of the above-mentioned points, an object of the present invention is to simultaneously invalidate the print records output since the execution of the previous commit instruction when a commit instruction or roll bank instruction is executed for a database file, thereby updating the report file. The object of the present invention is to provide a commit synchronization control method for outputting a report file that enables the establishment of a static point.

[Means to solve the problem]

The commit synchronization control method for report file output of the present invention is a commitment control method that performs record lock management of a database file, and the commit synchronization control method performs actual updating of the database file and releases record locks to establish a quiescent point of the database file. a report commit control means for establishing a quiescing point of the report file by actually outputting a print record to a report file when the command is executed; and quiescing the database file by invalidating data updates after the immediately preceding quiescing point of the database file report rollback control means for establishing the rest point of the report file by invalidating the output of print records after the immediately preceding rest point of the report file when a rollback command for establishing the rest point is executed; and the report commit control means from a program. and report rollback control calling means for calling the report roll bank control means from a program.

[Effect]

In the report file output commit synchronization control method of the present invention, the report commit control means updates print records to the report file when executing a commit instruction that actually updates the database file, releases the record lock, and establishes a quiescent point for the database file. The report rollback control fl1 means disables data updates after the previous quiescing point of the database file and establishes the quiescing point of the database file by performing actual output. , the report commit control calling means calls the report commit control means from the program, and the report rollback control calling means causes the report rollback from the program. Invoke control means.

〔Example〕

Next, the present invention will be explained in detail with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of an embodiment of the commit synchronization control method for outputting a report file according to the present invention.

The commit synchronization control method for outputting a report file in this embodiment consists of a user program 1, a commit instruction 2 included in the user program 1, a report commit control calling means 3 included in the commit instruction 2, and a user program 1. a rollback instruction 4 included in the rollback instruction 4, a report roll bank control calling means 5, a database commit control means 6, a commit control means 7, and a database commit control means 8 included in the rollback instruction 4.
, report roll bank control 1 means 9, file management table 10, report buffer 11, database file 12, report file 13, report actual output means 14, printing device 15, and save area 1
The main part is composed of 6.

Next, the operation of the commit synchronization control method for report file output according to the present embodiment configured as described above will be explained.

When commit instruction 2 is executed in user program 1,
Database commit control means 6 is called.

The database commit control means 6 performs actual updating of the database file 12 and releases all record locks, and establishes a quiescent point for the database file 12 (for example, outputs a journal to a journal file (not shown)).

At the same time, the report commit control calling means 3 in the commit instruction 2 calls the report commit control means 7 and transfers control thereto.

When the report commit control means 7 receives control from the report commit control calling means 3, it writes the contents of the report buffer 11 to the report file 13 and establishes a quiescent point for the report file 13 (for example, when the report file 13 is stored). write the final block address in the volume inventory of the polyneme that is being used). At this time, the report commit control means 7 controls the report buffer 1
If the number of print records corresponding to one block has not been output in 1, the unoutput record part of the print record is padded with characters indicating that the record is empty, and then the block unit is printed in the report file 13. Export records. Note that if the report buffer 11 is completely empty, print records are not written in blocks to the report file 13. Next, the report commit control means 7 saves the contents of the file management table 10 and the contents of the report buffer 11 to the save area 16.

The report commit control means 7 establishes a quiescent point for the report file 13, and the contents of the report file 13 at the time of execution of the commit command 2 are guaranteed, so that an abnormality in the user program I or the database system goes down after this. However, the print records in the report file 13 are still saved, and after the user program 1 is re-executed or the database system is restarted, the saved print records are sent to the printing device 1 by the report actual output means 14.
5 can be printed out as report output information.

Thereafter, when the rollback instruction 4 is executed by the user program 1, the database rollback control means 8 is called.

The database roll bank control means 8 establishes a quiescent point of the database file 12 by invalidating data updates after the immediately previous quiescent point of the database file 12 (
For example, restoring the contents of the journal file to the database file 12).

At the same time, the report rollback control calling means 5 in the roll bank instruction 4 calls the report rollback control means 9 and transfers control thereto.

When the report rollback control means 9 receives control from the report roll bank control calling means 5, the report rollback control means 9 transfers the contents of the file management table IO saved in the save area 16 and the contents of the report buffer 11 to the file management table 10 and the report buffer. 11 and 11 respectively.

Therefore, the file management table 10 and report buffer 11 are returned to the state at the time of execution of the immediately previous commit instruction 2, and print records requested to be output after the immediately previous execution of the commit instruction 2 are invalidated. In other words, the print records stored in the report buffer 11 are invalidated by restoring the report buffer 11, and the print records already written to the report file 13 are invalidated by restoring the file management table 10, and the blocks of print records after that are invalidated by restoring the report buffer 11. Overwritten by unit writing.

Next, the processing in the report commit control means 7 and the report roll bank control means 8 will be explained in more detail with reference to FIG. Note that here, the report buffer 11 can store three print records a, print record b, and print record C, and the report buffer 11 is full of print records a, print record b, and print record C. Assume that the three stored print records a, print record b, and print record C are written as one block in the report file 13.

After the report commit control means 7 outputs print record #4 to the report file 13, commit command 2 is issued.
When the report commit control means 7 is called based on the execution (commit request), the file management table lO
and the contents of the report buffer 11 are saved to the save area 16. Further, the contents of the report buffer 11 are output to the report file 13, but since print records b and print records C on the report buffer 11 are empty records, they are padded before being output.

Further, the contents of the file management table IO are updated so that the next block output is block B2.

After this, when there is a request to output print record #5 and print record #6, block B2 is transferred to the report file 13.
It is written out again to the upper block B2.

Furthermore, when the report rollback control means 9 is called based on the execution of the rollback instruction 4 (rollback request) after there is a request to output print record #7 (not shown), the report is saved in the save area 16. The file management table 10 and the report buffer 11 are created by the contents of the file management table 10 and the contents of the report buffer 11.
is restored to the state immediately after the commit request.

After that, when an output request is made for print record #8 (not shown), it is stored in the position of print record b in the restored report buffer 11, and is printed after the output request for print record #9 (not shown) is made. Record quality 4. Print record #
8 and print record #9 of report file 13.
It is output to block B2. As a result, a print record is attached5. Print record #6 and print record #7 are deleted.

In this way, even if an error occurs in user program 1 or the database system goes down after executing commit instruction 4 after outputting print record #4, print record #
The contents up to 4 are output to the report file 13 and guaranteed.

C. Effects of the Invention] As described above, the present invention provides a report commit control means for actually outputting a print record to a report file when a commit command is executed and establishing a quiescent point of the report file, A report rollback control means for disabling the output of print records after the immediately previous resting point of a file and establishing a resting point for a report file, a revotocomint control calling means for calling a report commit control means from a program, and a report roll bank control from a program. By providing a report roll bank control calling means for calling the means,
Even if output to a report file is executed in a program regardless of the time of a commit request to a database file or a roll bank request, the contents of the report file will not conflict with the contents of the database file, improving program productivity. There are effects that can be greatly improved.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of an embodiment of the report file output commit synchronization control method of the present invention, and FIG. 2 explains the processing of the report commit control means and report rollback control means in FIG. 1. This is a diagram for In the figure, 1... User program, 2... Commit instruction, 3... Revolution command control calling means, 4... Rollback instruction, 5... Report rollback control calling means, 6.・
- Database commit control means, 7... Report commit control means, 8... Database rollback control means, 9...
Report rollback control means, 10... File management table, 11... Report buffer, 12... Database file, 13... Report file, 14... Report actual output means, 15... Printing device , 16... This is a save area.

Claims (1)

[Scope of Claims] In a commitment control method that manages locking of records in a database file, when a commit instruction is executed to actually update the database file, release the record lock, and establish a quiescent point of the database file, the database file is transferred to a report file. report commit control means for actually outputting print records of and establishing a quiescing point for the report file; and a rollback instruction for invalidating data updates after the immediately preceding quiescing point for the database file and establishing the quiescing point for the database file. report rollback control means for establishing a resting point of the report file by invalidating the output of print records after the immediately preceding resting point of the report file during execution; and report commit control calling means for calling the report commit control means from a program. and a report rollback control calling means for calling the report rollback control means from a program. A commit synchronous control method for outputting a report file.