JPH06231027A - Exclusive control method - Google Patents

Abstract

(57) [Summary] [Object] The present invention realizes a data exclusive control mechanism by specifying a range in a file in a system in which a plurality of programs can access a file having no concept of a record. It features data consistency for files without the concept of records. [Structure] When accessing data in a file 1 from a program (file access mechanism) 11, a data search unit 12 checks whether or not a designated data area is used by another program, and the unused ( If not registered), the data registration unit 13 causes the file 1
The specified data area (the beginning and the end of the data) to be accessed in is stored in the data storage area 15, and the data to be accessed in the file 1 is represented by the relative position in the file. It is characterized by managing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exclusive control method for data in a file applied to a system which allows a plurality of programs to access a file having no concept of record at the same time.

[0002]

2. Description of the Related Art Conventionally, in accessing a file, data is referred to or updated in record units. In a system where multiple programs (file access mechanism) can access the same file, one record or one block is represented by a certain key and the key value is managed in order to ensure data consistency. By this, exclusive control is performed for file access from multiple programs.

As described above, in access control of a file having the concept of a record, data can be managed on a record-by-record basis. However, for a file that does not have the concept of a record, a plurality of programs share the same data. When accessing, exclusive control cannot be managed for each data unit.

[0004]

As described above, in the past, when accessing the same data from a plurality of programs in a file that does not have the concept of a record,
There was a problem that exclusive control could not be managed for each data unit.

The present invention has been made in view of the above circumstances,
It is an object of the present invention to provide a key exclusive control method that enables range specification and enables exclusive control in access data units for files that do not have the concept of records.

[0006]

SUMMARY OF THE INVENTION The present invention relates to an input / output control mechanism (file access mechanism) from a program executing a certain process in a system in which a plurality of programs can access a file having no concept of record. ), The data area to be accessed in the file starts at the relative position in file 1 (tip).
And the end (termination), and when accessing the data in the file 1, a data retrieval processing means for checking whether the data area is already used by another program, and a data retrieval processing means for the designated area. When access is possible, the data registration processing means for storing the data area to be accessed (head and end of access data) in the system, and releasing the access data area from the system when the access to the data is completed And a data deletion processing means for performing the exclusive control in units of access data with respect to a file having no record concept to ensure data consistency.

[0007]

In a system in which a plurality of programs (file access mechanism) can access a file without the concept of a record, when a program having a certain processing function accesses the above file, the access data is stored in the file as a relative file. Expressed by position, exclusive control is performed by specifying the range.

By managing the access data by designating a range at the start position and the end position of the data,
As shown in, the data can be checked by a simple determination of the magnitude relation. By enabling exclusive control of data by specifying a range in this way, data consistency can be ensured for files without the concept of records.

[0009]

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 the present invention.

In FIG. 1, reference numeral 1 denotes a file which is accessible from a plurality of programs (file access mechanism) and has no record concept. Reference numeral 2 is access data in the file 1, and the data area of the access data (the head and the end of the access data) is represented by the relative position in the file 1.

Reference numeral 11 is a program for accessing data in an arbitrary area to the file 1 having no record concept. Here, it is shown as a file access mechanism for controlling access to the file 1 in accordance with a request from a program for executing a predetermined process. There is.

Reference numeral 12 is a data retrieval unit for checking whether or not the data area to be accessed of the file 1 has already been accessed. Here, the relative position in the file 1 stored in the data storage area 15 is used. Represented access data area (start (top) of access data
And end (termination), it is checked whether or not the data area to be accessed includes the currently accessed data area.

A data registration unit 13 stores the access area of the file 1 in the system. Here, the access data area (start and end of access data) is represented by a relative position in the file 1 and is stored in the data storage area 15. Store and register / manage on the data storage area 15. 14
Is a data release unit that deletes the access area from the system, and releases the accessed data area on the data storage area 15.

Reference numeral 15 is a data storage area for storing an access data area (start and end of access data) represented by the relative position of the file 1, which is referred to by the data retrieval section 12 and accessed by the data registration section 13. Is stored (registered), and the data release unit 14 deletes (releases) the access data area.

FIG. 2 is a diagram for explaining the operation of the embodiment of the present invention, in which A is stored (registered) in the data storage area 15.
The start position (tip position) of the access data area in the created file 1, B is the end position (end position) of the same area,
a1 to b1, a2 to b2, ... Represent data areas subject to exclusive control by the access data areas (A to B).

3 and 4 are flow charts showing the processing procedure of the above embodiment, FIG. 3 is a flow chart showing the processing procedure of storing the access data area in the above embodiment, and FIG. 4 is the above embodiment. 5 is a flowchart showing a procedure for deleting an access data area.

Storage processing of the access data area shown in FIG. 3 is performed by the data registration unit 13. In FIG.
S1 is a step of designating the access data, which designates and designates the access data area (start and end of the access data) by relative positions in the file 1. S2 is a step of checking the access data, and it is checked whether or not the designated access data area has already been accessed in the system. S4 is a step of storing data, and a new access data area is registered in the data storage area 15 in the system.

The process of deleting the access data area shown in FIG. 4 is performed by the data release unit 14. In FIG.
Step S11 is a step of designating release data, in which the data area to be released (the head and the end of the release data) is expressed and designated by the relative position in the file 1. S13 is a step of releasing the data, and when the access to the data area registered in the data storage area 15 is completed, the data area is deleted from the data storage area 15. The operation of the embodiment of the present invention will be described with reference to FIGS.

When the file 1 is shared and used by a plurality of programs, access data is managed for each file and exclusive control is performed in data units in order to maintain consistency of data being accessed.

The feature here is that the data to be accessed in the file 1 is represented by the relative position in the file, as means for identifying the data for exclusive control.
Manage at the beginning and end of data.

Program (file access mechanism) 11
When the data in the file 1 is accessed from the program 1, the program (file access mechanism) 11 specifies the data area (relative position) of the file 1 (step S1 in FIG. 3).
).

The data retrieval unit 12 checks whether or not the designated data area is used by another program (step S2 in FIG. 3). If it is unused (unregistered),
Control is passed to the data registration unit 13 and the data registration unit 13
Stores the designated data area (the beginning and the end of the data) to be accessed in the file 1 in the data storage area 15 (step S4 in FIG. 3).

Here, since the access data area (the head and the end of the data) is stored in the data storage area 15 because the relative positions in the file 1 are stored, if the data are arranged in ascending order, all of them are judged by the size. You don't have to check the registration data.

As shown in FIG. 2, when the data (A to B) are already registered, the data (a1 to b1) area, the data (a2 to b2) area, and the data (a3 to b3) area are stored. If you try to register any of them, an error will occur because each area of the data (a1 to b1, a2 to b2, a3 to b3) to be registered contains part or all of the registered data (A to B). , Or weight. This is A and an
, B and bn are checked for error. That is, when (A <bn <B) and (A <bn <B), an error or a wait occurs.

When the access to the data in the file 1 is completed, the accessed data area is deleted from the data storage area 15, and the accessed data area is returned to the unused state and released.

As described above, the exclusive control is performed by the access data area (the head and the end of the data), so that even if the file 1 without the concept of a record can be accessed by a plurality of programs, the data in the file 1 is always stored. Be consistent.

[0027]

As described above in detail, according to the present invention, in a system in which a plurality of programs can access a file that does not have the concept of a record, an exclusive control mechanism for data by specifying a range in the file is provided. By realizing it,
Data consistency can be achieved for files without the concept of records.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a main part according to an embodiment of the present invention.

FIG. 2 is a diagram for explaining the operation of the above embodiment.

FIG. 3 is a flowchart showing a storage processing procedure of an access data area in the above embodiment.

FIG. 4 is a flowchart showing a procedure for deleting an access data area in the above embodiment.

[Explanation of symbols]

1 ... file, 2 ... access data in file 1, 1
1 ... Program (file access mechanism), 12 ... Data search unit, 13 ... Data registration unit, 14 ... Data release unit,
15 ... Data storage area.

Claims (1)

[Claims] 1. A system for allowing a plurality of programs to access a file having no concept of a record at the same time, and a file access means for accessing data in the file by relative position in the file, and the file. Exclusive access control is performed by referring to the access data area registered in the data registration means when accessing the file, and the data registration / release means for managing the access data area in the access data at the start end position and the end position of the access data. An exclusive control method of a file without a record concept, characterized by comprising exclusive control means for performing.