JP2000293426A - Record lock method - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To improve the reliability of a database and to improve the operability of database access from a browser via a CGI by enabling a lock required for updating a database by a CGI. Let it. The present invention includes a database access control execution unit (CGI program), a transaction management unit, a time monitoring unit, a lock management control structure, and a database access control unit, and the CGI is configured to access a database record. Operate to enable free lock control.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an HTML (Hyper Text Markup Language) existing in a WWW (World Wide Web) server from a browser on a client computer.
The present invention relates to a technique for operating a CGI to refer to and update a database when accessing a file.
Record locking method for locking database records by the system.

[0002]

2. Description of the Related Art In the prior art, when accessing a database from a browser via a CGI, there is a high possibility that the browser is terminated by a user. Therefore, the CGI process is terminated while the CGI is locking the database. Therefore, the CGI cannot perform a lock required when updating the database, and there is a problem in reliability and operability of the database.

[0003]

In the processing by the CGI, there is a problem that a lock necessary for updating a database cannot be performed. The reason is that in the processing by CGI, the CGI process is executed for each request from the client, so that even if the database is locked, if the CGI process is terminated by the request from the user, the database cannot be unlocked. It is.

An object of the present invention is to improve the reliability of a database and to improve the operability of database access via a CGI from a browser by enabling a lock required for updating a database by the CGI. The purpose is to let them.

[0005]

According to a first record lock method of the present invention, a database access control execution means includes:
A transaction management unit, a time monitoring unit, a lock management control structure, and a database access control unit are provided, and a CGI (Common Gateway Interface) can freely control a lock on a database record.

[0006]

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

Referring to FIG. 1, the embodiment of the present invention includes a client computer 100 on which a browser 101 operates, and a WWW server management means 104 which holds an HTML file 102 and controls and controls the reference of the HTML file from the browser. Server computer 103
A database access control execution unit (hereinafter referred to as CGI) 105 which is appropriately executed by referring to the HTML file based on the WWW server management unit, and a database access execution unit (hereinafter referred to as transaction) from the CGI
Management means 106 for managing the transaction, and database access control means 109 activated for each transaction from the CGI based on the transaction management means.
A lock management control structure 108 for recording information necessary for the database access control means to control the database lock state of the CGI, a time monitoring means 107 for monitoring the database record lock state and performing the necessary lock control. And a database 110 that stores data that is referenced and updated from a browser via an HTML file and a CGI.

[0008] These means operate as follows.

When a user refers to an HTML file from a browser and refers to a record of a specific table in a database with updating, the WWW server management means 104 activates a CGI required for the reference, and Information, table information and record information are input to this means.

[0010] The CGI is used by the transaction management means 10.
In order to allow the user to access the database, an access execution unit identifier (hereinafter, referred to as a transaction identifier) for the database is acquired for the user.

The means 106 comprises a transaction identifier,
Using the table information and the record information as input information, the database access control means 109, which is a processing means for accessing the database, is started.

[0012] The means 109 adds a transaction identifier acquired earlier by the CGI and executes a reference to the specified record of the specified table with an update to the specified record of the specified table every time the database is accessed. Is recorded in the lock management control structure 108 (locked state is set), a record search is executed on the database 110, and time monitoring is started using the time monitoring means 107.

Reference of the record from another user is as follows:
According to the information of the lock management control structure 108, the means 109
Can be rejected by

Normally, in response to an end of reference to an HTML file from a user, a lock release request executed by the CGI causes the means 109 to reset the locked state recorded in the lock management control structure and stop the means 109.

If the user terminates the browser with the record locked, the time monitoring means 107
Detects that the record lock has not been released by the user for a certain period of time, resets the locked state, and simultaneously stops the means 109.

Next, the lock control processing of the present embodiment will be described in detail with reference to the flowcharts of FIGS.

FIG. 2 is a flowchart of the lock control process of the database access control means 109.

When a database access request is issued from the CGI to the means 109, it is confirmed from the specified table information and record information whether the record is locked from the lock management control structure. If the record is locked, the designated transaction identifier is checked to determine whether the request is a request from the user who locked the record.

If the users are the same user, this database access request is processed.

If the user is another user, the request is rejected.

If the record is not locked, the transaction identifier, table information, and record information are recorded in the lock management control structure, the record is locked, and the time monitoring means 107 starts a timer for a fixed time. Then, the access of the record is executed.

FIG. 3 is a flowchart of the lock release processing. When the database access control unit 109 receives a lock release request from the CGI, it clears the corresponding information in the lock management control structure, puts the record in the unlocked state, and stops the unit 109. Further, when the user terminates the access to the database while the lock is applied, the time monitoring unit 107 detects this event by the timeout of the timer, and makes a pseudo unlock request to the unit 109. Means 1 receiving this request
09 performs the same processing as a lock release request from a normal CGI.

Next, a second embodiment of the present invention will be described in detail with reference to the drawings.

Referring to FIG. 4, according to a second embodiment of the present invention, the CGI program of the means 105 of FIG. 1 is replaced with a database access control executing means (Active) implemented by an ActiveX development environment provided by Microsoft Corporation.
vX program) 205. The means 105 and 205 play the same role, but differ in the means of implementing the program.

Next, a third embodiment of the present invention will be described in detail with reference to the drawings.

Referring to FIG. 5, in a third embodiment of the present invention, the CGI program of the means 105 shown in FIG. 1 is executed by a database access control execution means (A) realized by a Java development environment provided by Sun Microsystems. Ja
va program) 305.

The functions of the means 105 and 305 are the same, but the means for realizing the program is different.

[0028]

According to the present invention, the lock required for updating the database by the CGI can be performed, thereby improving the reliability of the database and improving the operability of the database from the browser via the CGI. That is. The reason is that the CGI for locking the database is recorded for each processing request, and the lock state is monitored over time, so that the CGI can be performed while the database is locked.
This is because the database can be automatically unlocked even after the GI process ends.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a first exemplary embodiment of the present invention.

FIG. 2 is a flowchart showing a part of the operation of the first exemplary embodiment of the present invention.

FIG. 3 is a flowchart showing a part of the operation of the first exemplary embodiment of the present invention.

FIG. 4 is a block diagram showing a configuration of a second exemplary embodiment of the present invention.

FIG. 5 is a block diagram showing a configuration of a third exemplary embodiment of the present invention.

[Explanation of symbols]

Reference Signs List 100 client computer 101 browser 102 server computer 103 HTML file 104 WWW server management unit 105 database access control unit (CGI program) 106 transaction management unit 107 time monitoring unit 108 lock management control structure 109 database access control unit 110 database 205 database access control Means (Active
X program) 305 Database access control means (Java program)

Claims (1)

[Claims] 1. A database access control execution means,
A record comprising a transaction management means, a time monitoring means, a lock management control structure, and a database access control means, wherein a CGI (Common Gateway Interface) can freely control a lock on a database record. Lock method.