JPH0512094A - Transaction managing device - Google Patents

Abstract

PURPOSE:To shorten the waiting time of another terminal by transmitting an answer signal for negating the execution of a transaction to another user's terminal together with a message of a fact being in the course of lock in the case of outputting a transaction from other user when the transaction is locked extending over a long period. CONSTITUTION:A register R provided on the inside of a transaction managing device 5 sets an ID number transmitted from a terminal which necessitates a lock for a long time, and a flag register FR registers a fact of a locking state of a long time. In such a state, when the transaction from respective terminals A-C is received, the bit of the flag register FR is confirmed, and in the case of the transaction of a long time, the fact of a locking state is transmitted to a user's terminal.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to an apparatus for managing transactions from multiple users to a database.

[0002]

2. Description of the Related Art The work performed by a user on a database is called a transaction. Broadly, it refers to a processing request such as data search for a database, and a series of operations from execution of processing to confirmation of completion of processing, and narrowly refers to the processing request itself. In this specification as well, a transaction means a processing request to a database or processing itself, and is used to receive a transaction, execute a transaction, and the like. Since the database is created for the purpose of sharing data among multiple users, transactions from each user occur randomly. Therefore, a device for managing these transactions and sequentially executing them is attached to the database. The conventional transaction management will be described below with reference to FIG.

Transaction management is performed by a database management unit 2 that accesses the database 1. Using this database management unit 2 as an interface, each computer terminal A, B, C provided on the user side. (Hereinafter, simply referred to as terminals A, B, and C) and the database 1 are connected to each other via a data communication line 3. Now, let us say that the transaction output from the terminal A is TR1, the transaction output from the terminal B is TR2, and the transaction output from the terminal C is TR3.

The database management unit 2 executes the transactions in the order in which they are received. For example, when the transactions TR2 and TR3 are output from the terminals B and C during the execution of the transaction TR1, these transactions TR2 and TR3 are output. After receiving, it is temporarily stored in the buffer 4. Then, after the transaction TR1 is completed, the transaction TR in the buffer 4 is
2 and TR3 are sequentially processed.

This is because if a user executes a transaction from another user while a user is registering or changing data in the database 1, the registration location or change will be wrong. is there. Therefore, while the transaction TR1 is being executed, the database 1 is passed to and occupied by only the terminal A that has output the transaction TR1, and the other terminals B and C are placed in a waiting state. This is called a transaction lock state, and is one of the processes required to manage transactions from multiple users.

[0006]

However, when the transaction lock state is long, for example,
When enormous amounts of data are collectively registered in the database 1 or when data in the database 1 is changed, the waiting time of other terminals can be long and other work can be performed in the meantime. Therefore, there is an inconvenience that work efficiency is reduced.

[0007] Normally, a user accesses a database 1 as needed while executing a certain program toward a terminal. That is, the transaction with respect to the database 1 is an "interrupt process" arbitrarily generated by the operator's intention during the execution of the program. Therefore, the program being executed remains suspended until the end of the transaction, resulting in the above inconvenience.

The present invention has been made in view of the above circumstances, and provides a transaction management apparatus for improving the work efficiency by eliminating the waiting time of other terminals when the transaction lock state is long. The purpose is to provide.

[0009]

In order to achieve the above object, the present invention has the following constitution. That is, the present invention is a transaction management device that prohibits execution of transactions from other users (locks transactions) while executing transactions from users to the database, and locks the transactions for a long time. A first judging means for judging whether the transaction is from the other user, and a second judging means for judging that a transaction from the other user is output when a lock for a long time is judged by the first judging means. Based on the judgment means and the judgment of the second judgment means, a transmission means for transmitting a message indicating that the transaction is locked to the computer terminal of another user and a response signal for denying the execution of the transaction. It is characterized by having and.

[0010]

The function of the present invention is as follows. When a user outputs a transaction to the database, the transaction management device causes the user to occupy the database and prohibits the execution of the transaction by other users (locks the transaction). At this time, the first judging means judges whether the transaction is locked for a long time, and the second judging means outputs a transaction from another user during the long locking. Make a decision. Based on the judgment of the second judging means, the transmitting means transmits a message indicating that the transaction is locked and a response signal denying the execution of the transaction to the computer terminals of other users.

[0011]

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 a schematic configuration of a database system including a transaction management device of the present invention. In addition, in FIG.
Those denoted by the same reference numerals as are the same components. As shown in the figure, transaction management, which has been a partial function of the database management unit 6 in the past, is separated from the database management unit 2 and configured as an independent device. A register R provided inside the transaction management device 5 sets an ID number transmitted from a terminal that requires a long-time lock, and a flag register FR registers that it is in a lock state for a long time. The operation of the transaction management device 5 will be described below with reference to the flowchart of FIG.

When a transaction is received from each of the terminals A to C (step S1), it is judged whether or not the transaction is currently in a locked state for a long time (step S2). This is determined by whether or not the bit is set in the flag register FR. If the locked state is for a long time, the process proceeds to step S8, and if the locked state is not for a long time, the process proceeds to step S3.

In step S3, it is determined whether or not the transaction input in step S1 requires a long-time lock. This determination is made according to the type of transaction, that is, the type of processing request to the database 1. A processing request that requires a long-time lock is determined in advance, and the request statement is already registered in the transaction management device 5. For example, it is a processing request such as full-text registration or data change. The transaction management device 5 performs matching processing between the processing request input in step S1 and a request statement registered in advance, and determines that the transaction is a long transaction if there is a match and a short transaction if there is no match. ..

If the transaction is for a long time, the process proceeds to step S4, a message indicating that the lock state is set is transmitted to other terminals, and a bit is set in the flag register FR (step S4).
5), the ID number from the terminal that outputs the transaction is set in the register R (step S6). When accessing the database 1, the user usually sends the ID number given to him / her together with the transaction from the terminal, and the transaction management device 5 gives the ID number of the user who needs a long lock. Register in register R. Then, in step S7, the transaction is passed to the database management unit 6 and executed.

On the other hand, when it is determined in step S3 that the transaction is a short time (when the transaction is data retrieval or partial registration), the process jumps to step S7, and the transaction is passed to the database management unit 6 to be processed. Run. Since it is known that the waiting time of other terminals is short if it is a short-time transaction (generally about several seconds for data search, while it is about several minutes to tens of minutes for long-term transaction), the transaction is the same as before. Will be executed in the order received.

Then, the process returns to step S1. If it is determined that the transaction received in the above process is a transaction that requires a long lock, a bit is set in the flag register FR, so that the next (second) transaction is received. The process proceeds from step S2 to step S8.

In step S8, it is determined whether or not the transaction is from a user who is locking the transaction. This is determined by the matching process between the ID number sent with the next transaction and the ID number set in the register R. If they match, it is determined that the transaction is from the user who is locking, and the process proceeds to step S7 to execute the transaction. If they do not match, the transaction is considered to be from another user and the process proceeds to step S9.

In step S9, a message indicating that the transaction is locked is transmitted to the request source, that is, the terminal that has output the transaction, and then a response signal that denies execution of the transaction is transmitted (step S9).
Ten) . As described above, since the transaction to the database 1 is the “interrupt processing” for the terminal, once the transaction is received, it waits until it is completed. In order to avoid this waiting state, if the terminal is locked for a long time, a signal for interrupting the "interrupt processing" of the terminal, for example, a negative response signal that the transaction has not been received is output. The terminal receiving the negative response signal interrupts the transaction to the database 1 and returns to the execution of the original program.

In addition to the configuration of the above-mentioned embodiment, a lock release message may be output to each terminal when the lock is released for a long time.

As is apparent from the above description, the transaction management device of the present invention is in the lock state when the transaction is locked for a long time and a transaction from another user is issued. Since the response signal denying the execution of the transaction is transmitted to the computer terminal of the other user together with the message, the computer terminal of the other user interrupts the transaction to the database. Therefore, other users can continue their work on the computer terminal without waiting for a long time until the lock is released, and the work efficiency is improved.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of a database system including a transaction management device of the present invention.

FIG. 2 is a flowchart showing functions of a transaction management device.

FIG. 3 is a schematic block diagram of a database system for explaining conventional transaction management.

[Explanation of symbols]

 1 ... Database 5 ... Transaction Management Device A, B, C ... Computer Terminal

Claims (1)

What is claimed is: 1. A transaction management device that prohibits execution of a transaction from another user (locks a transaction) while a transaction from a user to a database is being executed. For a long time, and if the first judgment means determines a long-time lock, the transaction from the other user is output. Second to judge
Based on the determination means of the second determination means and the determination means of
A transaction management device comprising: a transmission means for transmitting a message that a transaction is locked to a computer terminal of another user and a response signal that denies execution of the transaction.