JP2000047918A - Replication system and replication control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make exactly performably operating manipulations on the side of a replica data base(DB) on a reflected side synchronously with the updating condition of a master DB. SOLUTION: When the update of a master DB is detected and the update information is extracted and stored in an update information file 6 by a replication extracting function part 7, a replication reflection control function part 8 inputs the update information from the update information file 6 and makes the update information reflect in the replica DB or replica DB 4 of a replica server 3. Similarly, the replication reflection control function part 8 extracts manipulation information from an event information table 12 in which the manipulations are previously registered corresponding to events by making the update information as a key and successively executes the stipulated manipulations.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a replication system and a replication control method, and more particularly, to a replication system and a replication control method.
The present invention relates to a replication system and a replication control method in which a replica database is automatically updated when a master database is updated.

[0002]

2. Description of the Related Art When a master database is updated by transaction processing or the like, a replica database is automatically updated. When a master database is updated, the update information is reflected in the replica database. It is necessary to perform operations based on events that accompany the update of the master database.
The reflection of the update information of the master database to the replica database and the operation by the event accompanying the update of the master database are independently and asynchronously executed.

[0003] As a conventional technique relating to this type of replication system, for example, a technique described in "Nikkei Electronics 1994.6.6 (No.609), Masahiro Nakamura, pp. 101-110" is known. ing.

[0004]

The prior art described above is
Various operation operations on the replica database on the reflection side synchronized with the update conditions of the master database are not taken into account, and the operation on the replica database on the reflection side is performed in synchronization with the update conditions on the master database However, there is a problem that the replica database, which is the reflection side, cannot know the operation status of the master database, such as a break in updating the master database, and cannot operate the replica database accurately. .

An object of the present invention is to provide a replication system which solves the above-mentioned problems of the prior art, and which allows an operation operation on a replica database on a reflection side to be performed accurately in synchronization with an update condition of a master database. And a replication control method.

[0006]

According to the present invention, an object of the present invention is to provide a replication system for updating a replica database which is a duplicate database of a master database when the master database is updated. When loading
An event detection means for detecting update information defined as an event occurrence condition and reporting an event detection; and an event information file in which operations at the time of event occurrence are registered in advance using the event information reported from the event detection means as a key. And an event control means for reading and executing the operation information from the computer.

In addition, the above object is to provide a replication control method for updating a replica database which is a replica database when a master database is updated, wherein an event occurrence condition is set when reading update information of the master database for updating the replica database. The defined update information is detected, and the operation at the time of event occurrence is achieved by reading and executing the operation information from a previously registered event information file using the detected event information as a key.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a replication system according to the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of a replication system according to an embodiment of the present invention. FIG. 2 is a diagram for explaining the data configuration of an event activation definition file.
FIG. 4 is a diagram illustrating a data configuration of an event information file, FIG. 4 is a flowchart illustrating a processing operation of a replication control program, FIG. 5 is a flowchart illustrating a processing operation of a replication extraction function unit, and FIG. FIG. 7 is a flowchart illustrating the processing operation, and FIG. 7 is a flowchart illustrating the processing operation of the update information reflection function unit. 1 to 3, 1 is a master server, 2 is a master database (master D).
B), 3 is a replica server, 4 and 21 are replica databases (replica DBs), 5 and 13 are replication control programs, 6 and 14 are update information files, 7 is a replication extraction function unit, and 8 and 16 are replication reflection control functions. , 9 and 17 are event activation definition files, 10 and 18 are event activation definition tables, 11, 1
9 is an event information file, 12 and 20 are event information tables, and 15 is a replication reception function unit.

A replication system according to one embodiment of the present invention comprises a master server 1 and a replica server 3, as shown in FIG. The master server 1 includes a master DB 2, a replica DB 21 that is a duplicate DB of the master DB 2 and is used on the server side, a replication control program 5 that controls replication,
An update information file 6 and a replication extraction function unit 7 which is controlled by the replication control program 5 and outputs update information of the master DB 2 to the update information file 6
A replication reflection control function unit 8 that extracts update information of the master DB 2 from the update information file 6, edits the updated information, and reflects the updated information on the replica DB 21 or transmits the updated information to the replica server 3; An event start definition file 9 describing the occurrence conditions, an event start definition table 10 that is created by storing the information of the event start definition file 9 in the memory when the replication is started, an operation code for each event number, an execution content, and an operation An event information file 11 for storing event information describing timing, and an event information table 1 for storing and creating event information of the event information file 11 in a memory at the time of starting replication.
And 2.

The replica server 3 has a master DB 2
A replica DB 4 that is a replication DB of the server, a replication control program 13 that controls replication on the replica side, an update information file 14, and receives update information of a database from another server under the control of the replication control program 13 and updates the replica server. Replication reception function unit 1 that outputs to information file 14
5, a replication reflection control function unit 16 that reads and edits update information from the update file 14 in the same manner as the replication reflection control function unit 8 on the master server, updates the replica DB 4, or transmits the replica DB 4 to another replica server.
And the event activation definition file 17 on the replica server side
, An event start definition table 18, an event information file 19, and an event information table 20.

As shown in FIG. 2, the event start definition file 9 has an event occurrence item 201 and an event occurrence condition expression 202 corresponding to an event number 200.
Is specified. Event information file 1
1 shows an operation code 301, an execution content 302, an event number 300, as shown in FIG.
The operation timing 303 is specified.

Each of the operation codes 301 shown in FIG. 3 has the meaning of UAP: UAP activation REP: replication operation MES: message output ETV: event information issuance to another server TIM: timer WAIT NON: do nothing

The execution content 302 includes the operation code 30
1 describes the operation corresponding to the operation code UAP.
For S, output message contents
Describes the contents of the replication operation (stop, restart, etc.), and the operation code TIM describes the WAIT time. Nothing can be described for the operation code NON.

Further, the operation timing 303 specifies the execution timing of the execution content for the operation code, and the BEFORE specifies that the operation is executed immediately before the update information is reflected (the execution order is the description order). , AF
The TER specifies that the operation is performed immediately after the update information is reflected (the execution order is the description order).

Next, referring to the flowcharts shown in FIGS.
The processing operation of the replication control program, the processing operation of the replication extraction function unit, the processing operation of the reflection control function unit, and the processing operation of the update information reflection function unit started by the reflection control function unit will be described. Since the flow shown in FIG. 4 to FIG. 7 performs processing in cooperation as a whole, the processing of FIG. 4 to FIG. 7 will be described below as a series of processing.

(1) When the replication control program is started and the processing is started, an extraction task for realizing the replication extraction function unit 7 and a reflection task for realizing the replication reflection control function unit 8 are started (step). 401, 402).

(2) After activating the tasks in steps 401 and 402, the replication control program waits for a response from each task, and detects the presence or absence of a response from each task (step 403).

(3) The activated extraction task is the master D
B2 is monitored to check whether update information has been generated in the master DB2, and if there is update information, the update information in the master DB2 is stored in the update information file 6 (step 41).
1, 412).

(4) After being started, the reflection task inputs update information from the update information file 6 and determines whether or not the input information is update information of the master DB 2 (steps 501 and 502). .

(5) If it is determined in step 502 that the input information is update information of the master DB 2, it is determined whether the update information satisfies the condition of the event activation definition table 10 (step 503). .

(6) If it is determined in step 503 that the update information does not meet the conditions of the event activation definition table 10, the update information reflection function unit is started, and the update information is edited to reflect the update information. It is checked whether the output specification of the update information is reflected or transmitted (step 51).
1, 512).

(7) If it is determined in step 512 that the output specification is to be reflected, the SQL is assembled, the edited update information is reflected in the replica DB 21, and if the output specification is determined to be transmission, the editing is performed. The updated information is transmitted to the replica server 3 (steps 513 and 514).

(8) If it is determined in step 502 that the input information is not the update information of the master DB 2, and after the processing in steps 513 and 514, the reflection task
Wait for a certain time. After that, when the waiting for the time ends, the reflection task returns to step 501 and repeats the above-described processing (step 510).

(9) If it is determined in step 503 that the input information from the update information file 6 is the update information of the master DB 2 and the information meets the conditions specified in the event activation definition table 10, the reflection task Indicates that the replication control program 5 has event information recognition, event number 200 and operation position information (BEFOR).
E) is reported, and the system waits for a communication from the replication control program 5 (steps 505 and 506).

(10) When the response from the task is detected in the above-mentioned step 403, the replication control program 5 detects the response from the task, and the response is the notification of the recognition of the event information from the reflection task. Check if it is a notification of recognition of event information,
The event information table 12 is searched using the event number 200 as a key, and operation contents at the same operation timing as the operation position are obtained (steps 404 and 405).

(11) Replication control program 5
Executes the acquired operations in the order described, and reports the end of the event operation to the reflection task (step 40).
6, 407).

(12) When the reflection task waiting for communication from the replication control program 5 in step 506 receives a report of the end of the event operation in the processing of the replication control program 5 in step 407, the update information reflection function unit Step 511 described above by
514 are executed (step 507).

(13) The reflection task reports the event information to the replication control program 5 again, and reports the event number 200 and the operation position information (AFTER).
It is in a state of waiting for communication from the replication control program 5 (steps 508 and 509).

(14) The replication control program 5, which has been monitoring the response from the task again in step 403, checks whether the response from the task is a notification of recognition of event information from the reflection task, and If it is a notification of recognition of event information, the event information table 12 is searched using the event number 200 as a key, and operation contents at the same operation timing as the operation position are obtained (steps 404 and 405).

(15) Replication control program 5
Executes the acquired operations in the order described, and reports the end of the event operation to the reflection task (step 40).
6, 407).

According to the above-described embodiment of the present invention, when the update information is reflected in the replica DB, the master data DB
When the update information is input from the update information file 6 that stores the update information of the event and the update information of the event occurrence condition is detected, the operation is taken out from the event information table 12 in which the operation is registered in advance in correspondence with the event, and the operation is Since the execution is sequentially performed according to the instruction, the operation operation on the replica DB on the reflection side synchronized with the update condition of the master database becomes possible at the timing when the update information of the master DB is reflected on the replica DB.

[0033]

As described above, according to the present invention, the operation operation on the replica DB on the reflection side synchronized with the update condition of the master database at the timing when the update information of the master DB is reflected on the replica DB is realized. This makes it possible to reduce the operational burden on the system administrator.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a replication system according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating a data configuration of an event activation definition file.

FIG. 3 is a diagram illustrating a data configuration of an event information file.

FIG. 4 is a flowchart illustrating a processing operation of a replication control program.

FIG. 5 is a flowchart illustrating a processing operation of a replication extraction function unit.

FIG. 6 is a flowchart illustrating a processing operation of a replication reflection control function unit.

FIG. 7 is a flowchart illustrating a processing operation of an update information reflection function unit.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Master server 2 Master DB 3 Replica server 4, 21 Replica DB 5, 13 Replication control program 6, 14 Update information file 7 Replication extraction function part 8, 16 Replication reflection control function part 9, 17 Event start definition file 10, 18 Event Startup definition table 11, 19 Event information file 12, 20 Event information table 15 Replication reception function unit

Claims (2)

[Claims] When a master database is updated, a replication system that updates a replica database, which is a replica database of the master database, updates information defined as an event generation condition when reading update information of the master database for updating the replica database. An event detecting means for detecting and reporting an event detection; and an event for reading and executing operation information from an event information file in which an operation at the time of event occurrence is registered in advance using the event information reported from the event detection means as a key. A replication system comprising control means. 2. A replication control method for updating a replica database, which is a replica database when a master database is updated, includes an update information defined as an event occurrence condition when reading the update information of the master database for updating the replica database. And performing an operation at the time of occurrence of an event by reading operation information from an event information file registered in advance using the detected event information as a key.