KR102350282B1 - Apparatus and method for synchronization of multiple databases - Google Patents

Abstract

An embodiment of the present invention relates to an apparatus and method for synchronizing multiple databases, which suggests a reliable recovery method in case of a DB (replication) inconsistency during DB replication for DB synchronization or after completing the DB synchronization. The method for synchronizing multiple databases may include: (a) performing synchronization, when data is changed in at least one database (hereinafter, a first database) among multiple databases, by replicating the changed data in one or more other databases other than the first database (hereinafter, a second database); (b) displaying the changed data of the first database as specific information so that the changed data can be distinguished from the duplicate data of the second database; and (c) updating other data that is inconsistent based on the data in which the specific information is displayed, when the data corresponding to each other is inconsistent between the multiple databases.

Description

Apparatus and method for synchronization of multiple databases

The present invention relates to a technology for synchronization of multiple databases (Database: DB), and more particularly, mismatch of some field values may occur due to errors such as message loss during DB replication for DB synchronization or after DB synchronization is completed. , It relates to an apparatus and method for synchronization of multiple databases, which suggests a reliable recovery method in the event of such DB (replication) inconsistency.

In general, equipment installed in multiple offices in the network performs database synchronization in real time to provide the same data, and the results after DB sync must match.

That is, when data change occurs in at least one database among multiple databases corresponding to multiple equipment installed in multiple offices, the other database(s) also replicates the changed data and performs synchronization.

However, inconsistencies in some field values may occur due to errors such as message loss during DB replication for DB synchronization or even after DB synchronization is completed. There is a problem in that it is difficult to perform reliable recovery because it is not known whether the DB value should be matched based on the value.

Patent Publication No. 10-2012-0009666 (2012.02.02.)

The present invention is to solve the above-mentioned problems of the prior art, the purpose of which is to provide a reliable recovery method when DB (replication) inconsistency occurs during DB replication for DB synchronization or after DB synchronization is completed, for synchronization of multiple databases To provide an apparatus and method.

In order to achieve the above object, a method for synchronizing multiple databases according to an aspect of the present invention includes (a) when data change occurs in at least one database (hereinafter, first database) among multiple databases, the first database performing synchronization by replicating the change data in one or more other databases (hereinafter referred to as a second database); (b) displaying the changed data of the first database as specific information so that the changed data of the second database can be distinguished from the duplicate data of the second database; and (c) updating other data that is inconsistent based on data in which the specific information is displayed when discrepancy of data corresponding to each other between the multiple databases occurs.

In step (b), the specific information may be displayed in a tuple unit including change data, and in step (c), when there are a plurality of data in which the specific information is displayed, the latest (referring to the timestamp) Based on the change data, you can update other inconsistent data.

The step (c) may include: (c-1) acquiring data to be compared from one of the multiple databases (hereinafter referred to as a third database); (c-2) transmitting identification information for the obtained comparison target data from a third database to another database (hereinafter, referred to as a fourth database) of the multi-database; (c-3) querying the comparison target data from the fourth database based on the identification information and transmitting the searched data to the third database; and (c-4) finding inconsistent comparison target data after mutual comparison between each comparison target data among all comparison target data obtained by combining the comparison target data obtained from the fourth database and the comparison target data of the third database , updating and matching other inconsistent comparison target data based on the comparison target data in which the specific information is displayed, and the comparison target data may be data in tuple units.

In order to achieve the above object, an apparatus for synchronizing multiple databases according to another aspect of the present invention provides, when data change occurs in at least one database (hereinafter, a first database) among multiple databases, one or more other than the first database a synchronization unit for performing synchronization by replicating the changed data in another database (hereinafter, a second database); a marker for displaying the changed data of the first database as specific information to distinguish it from the duplicate data of the second database; and an update unit for updating other data inconsistent based on the data in which the specific information is displayed when the data inconsistency between the multiple databases occurs, wherein the marker unit includes a tuple ( The specific information may be displayed in units of tuple).

When there are a plurality of pieces of data in which the specific information is displayed, the update unit may update other data that is inconsistent based on the latest changed data (with reference to the timestamp), and compare it in one of the multiple databases (hereinafter, the third database) a data acquisition unit for acquiring target data; an information transfer unit configured to transmit identification information on the obtained comparison target data from a third database to another database (hereinafter, referred to as a fourth database) of the multi-database; a data transfer unit for inquiring the corresponding comparison target data from the fourth database based on the identification information and transmitting the searched data to the third database; and when the comparison target data obtained from the fourth database and the comparison target data obtained from the third database are compared with each other and inconsistent comparison target data is found among all comparison target data obtained by aggregating the comparison target data of the third database, the specific information may include a matching unit configured to update and match other comparison target data that do not match based on the displayed comparison target data, and the comparison target data may include data in tuple units.

According to another aspect of the present invention to achieve the above object, it is possible to provide a computer-readable recording medium in which a program for executing the method for synchronizing the multiple databases is recorded in a computer.

According to another aspect of the present invention in order to achieve the above object, it is possible to provide an application stored in a computer-readable recording medium in order to execute the method for synchronizing the multiple databases in combination with hardware.

In order to achieve the above object, according to another aspect of the present invention, it is possible to provide a computer program stored in a computer-readable recording medium in order to execute the method for synchronizing the multiple databases in a computer.

As described above, according to various aspects of the present invention, it is possible to determine the master DB, which can be a standard when a DB inconsistency between multiple databases occurs, so that even if the DB is inconsistent after DB sync, it can be corrected to the correct value. In this way, there is an effect of increasing the reliability of the DB data.

1 is a block diagram of a system for synchronization of multiple databases according to an exemplary embodiment of the present invention;
2 is a block diagram of an apparatus for synchronization of multiple databases according to an exemplary embodiment of the present invention;
3 is a detailed configuration diagram of the update unit of FIG. 2;
4 is a flowchart of a method for synchronization of multiple databases according to an exemplary embodiment of the present invention;
5 is a diagram for explaining an audit process according to an exemplary embodiment of the present invention.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings. In adding reference numerals to the components of each drawing, the same components are to have the same reference numerals as much as possible even though they are indicated in different drawings. In addition, when it is determined that a detailed description of a known configuration or function related to the embodiment of the present invention may obscure the gist of the present invention, the detailed description thereof will be omitted.

1 is a block diagram of a system for synchronization of multiple databases according to an exemplary embodiment of the present invention, and as shown in the figure, it includes a communication network 1, a synchronization server 2, and a database 3 can do.

The communication network 1 may be any single or complex network that enables communication by connecting the synchronization server 2 and the database 3 through wired, wireless and/or the Internet.

Synchronization server (2) is for reliable recovery in case of DB (database) synchronization between multiple databases (3) during DB replication or when DB (replication) discrepancy occurs after DB synchronization is completed. DB discrepancy between multiple databases (3) occurs By making it possible to determine the master DB, which can be the time standard, even if the DB is inconsistent after DB sync, it can be corrected to the correct value, thereby increasing the reliability of the DB data.

The database 3 represents the multiple databases DB1 to DBn 3 disposed in the communication network 1 , and may include, for example, multiple databases corresponding to multiple devices installed in various offices of the communication network.

Multiple databases (DB1 to DBn) (3) have to provide the same data to the equipment installed in multiple offices of the communication network (1), so the synchronization server (2) is between multiple databases (DB1 to DBn) (3). Database synchronization (DB sync) is performed in real time, and if the results after DB sync are inconsistent, it can be updated to match.

FIG. 2 is a block diagram of an apparatus for synchronizing multiple databases according to an exemplary embodiment of the present invention, and is a block diagram of the synchronization server 2 of FIG. 1 , and as shown in the drawing, a synchronizer 21 , a mark unit 23 , and an update unit 25 may be included.

When data change occurs in at least one database (hereinafter, the first database) among the multiple databases (DB1 to DBn) 3 , the synchronization unit 21 is configured in one or more other databases other than the first database (hereinafter, the second database). In order to perform synchronization by duplicating the change data, for example, when an example is described with reference to FIG. 5 , the identification information (ID) of 103 in the first database DB02 is a field forming a tuple of the same row. When data change occurs in at least one field among SVC1, SVC2, and SVC3, the second database DB01 and DB03 to DB08 as one or more other databases other than the first database DB2 replicate the change data to perform synchronization. have.

The marker 23 is for displaying the changed data of the first database as specific information so as to be able to distinguish it from the duplicate data of the second database, and the specific information is a tuple unit of the same row including a field of the corresponding changed data. can be displayed as

When an example is described with reference to FIG. 5 , the marker 23 displays L (Local) as specific information indicating data change in the tuple_origin field of the row that is the identification information 103 of the first database DB02 and R (Remote) as specific information indicating data replication may be displayed in the tuple_origin field of the row having the same identification information 103 of the second databases DB01 and DB03 to DB08 as other databases.

The update unit 25 is for updating other data that is inconsistent based on data in which specific information is displayed when there is a discrepancy in data corresponding to each other between the multiple databases DB1 to DBn 3 . Referring to FIG. 5 , one To explain the example, check the specific information displayed in the tuple_origin field of each of the multiple databases (DB1 to DBn) (3), and as specific information indicating data change among the multiple databases (DB1 to DBn) (3) Based on the data described in fields SVC1, SVC2, and SVC3 of the row with the identification information 103 of the database DB02 in which L is indicated, in the fields SVC1, SVC2, and SVC3 of the row with the corresponding identification information 103 of the other databases DB01 and DB03 to DB08, respectively It can be matched by updating the discrepancy data described.

The update unit 25 refers to the timestamp when inconsistency of data corresponding to each other between the multiple databases (DB1 to DBn) 3 occurs and there is a plurality of specific information L, other data that does not match based on the latest changed data can be updated

3 is a detailed configuration diagram of the update unit 25 of FIG. 2, as shown in the figure, a data acquisition unit 251, an information transmission unit 253, a data transmission unit 255, and a matching unit ( 257) may be included.

The data acquisition unit 251 is for acquiring comparison target data from one of the multiple databases (DB1 to DBn) (3) (hereinafter, the third database). Assuming that the third database, which is one of DB1 to DBn)(3), is the database DB01, data of all fields of the row (or tuple) having the identification information 103 of the database DB01 can be obtained as comparison target data.

The information transfer unit 253 transfers the identification information for the comparison target data obtained in the data acquisition unit 251 from the third database to another database (hereinafter, the fourth database) of the multiple databases (DB1 to DBn) 3 . 5, the identification information (ID) 103 of the row (tuple) obtained as comparison target data from the database DB01 as the third database is transferred to the databases DB02 to DB08 as the fourth database. can

The data transfer unit 255 inquires the corresponding comparison target data based on the identification information received from the third database in the fourth database and transmits it to the third database. In each of the databases DB02 to DB08 as databases, all data in the same row (tuple) as the identification information 103 received from the database DB01 as the third database can be searched as the corresponding comparison target data and delivered to the database DB01 as the third database, and the result is As shown in FIG. 5 , an audit table for monitoring whether or not matching of row (tuple) data corresponding to each other between databases DB01 to DB08 as multiple databases (DB1 to DBn) 3 may be provided.

The matching unit 257 compares all of the comparison target data of the third database and the fourth database and, when inconsistent comparison target data is found, compares other comparison target data that is inconsistent based on the comparison target data in which specific information is displayed In order to match by updating, for example, when an audit is attempted in database DB01 as a third database, some fields of SVC1, SVC2, SVC3 of databases DB03, DB04, and DB05 as in the audit table of FIG. It can be seen that the data value does not match the corresponding data value of the other database. When the discrepancy is confirmed in this way, the specific information displayed in the tuple_origin field of each of the multiple databases DB01~DB08 is checked, and the data value of the multiple databases DB01~DB08 is checked. Based on the data described in the fields SVC1, SVC2, and SVC3 of the row that is the identification information 103 of the database DB02 in which L as specific information indicating data change is indicated, the corresponding fields SVC1, SVC2, and SVC3 of the databases DB03, DB04, and DB05 are described The discrepancy data can be updated to match.

The coincidence unit 257 determines the database in which specific information L is written in the tuple_origin field of the audit table as shown in FIG. 5 as a reference master node, but when there are multiple databases in which L is written, the time By referring to the timestamp, it is possible to update other data that is inconsistent based on the data of the corresponding master node by determining that the most recent content is the master and the node.

As in the audit table of FIG. 5 , the matching unit 257 outputs the SQL (update for matching) statements to be executed in the databases DB03, DB04, and DB05 in the audit result report of the database DB01 to match them. , and the result of matching can be notified to the operator through MMI (Man Machine Interface).

In the present embodiment, the change data, duplicate data, or comparison target data has been described as an example of data in a tuple unit of a row, but is not limited thereto and may include data in various units including field units.

4 is a flowchart of a method for synchronization of multiple databases according to an exemplary embodiment of the present invention, which is applied to the synchronization server 2 device of FIGS. 1-3 and will be described in parallel with the operation of the device.

First, when data change occurs in the first database as at least one database among the multiple databases (DB1 to DBn) (3) (S401), the synchronization unit 21 is the first of the multiple databases (DB1 to DBn) (3). Synchronization is performed by replicating the corresponding changed data of the first database in the second database as a database other than the first database (S403).

Next, the marker 23 displays specific information on the changed data of the first database so that the changed data of the first database can be distinguished from the duplicate data of the second database, for example, as shown in FIG. In DB2 at the time 2019-11-17 18:12:25000056, when a change occurs in the data of at least one field among the identification information 103 row tuple, in the tuple_origin field of the row identification 103 of DB02 as the first database L (Local) as specific information indicating data change is displayed, and as specific information indicating data replication in the tuple_origin field of the row with the same identification information 103 of the second databases DB01 and DB03 to DB08 as other databases R (Remote) may be displayed (S405).

Next, the update unit 25 monitors whether a discrepancy occurs in data corresponding to each other between the multiple databases DB1 to DBn 3 ( S407 ), for example, the multiple databases as shown in FIG. 5 . An audit table is configured to monitor whether the row (tuple) data corresponding to each other between databases DB01 to DB08 as (DB1 to DBn)(3) is matched, and through the corresponding audit table, the It is checked whether the data corresponding to each other do not match (S409).

Finally, in step S409, as in the audit table of FIG. 5, the update unit 25 determines that the data values of SVC1, SVC2, and SVC3, which are some fields of the databases DB03, DB04, and DB05, are inconsistent with the corresponding data values of other databases. If one is confirmed, the specific information displayed in the tuple_origin field of each of the multiple databases DB01 to DB08 is checked, and L as specific information indicating data change among the multiple databases DB01 to DB08 is identified as 103 of the database DB02 Based on the data described in the fields SVC1, SVC2, and SVC3 of the row, the inconsistent data described in the corresponding fields SVC1, SVC2, and SVC3 of the databases DB03, DB04, and DB05 are updated to match (S411).

In step S411, when there are multiple databases in which the specific information L is written in the tuple_origin field of the audit table of FIG. Based on the data with the most recent time recorded in the (timestamp) field, other data that does not match is updated to match.

Meanwhile, according to the method for synchronization of multiple databases according to the embodiment of the present invention described above, a computer-readable recording medium in which a program for executing the method in a computer is recorded can be implemented.

On the other hand, according to the method for synchronization of multiple databases according to the embodiment of the present invention described above, an application stored in a computer-readable recording medium can be implemented in order to execute the method in combination with hardware.

On the other hand, according to the above-described method for synchronizing multiple databases according to an embodiment of the present invention, a computer program stored in a computer-readable recording medium can be implemented in order to execute the method in a computer.

For example, as described above, the method for synchronization of multiple databases according to an exemplary embodiment of the present invention is a computer-readable recording medium including program instructions for performing various computer-implemented operations or in such a recording medium. It can be implemented as a stored application. The computer-readable recording medium may include program instructions, local data files, local data structures, and the like alone or in combination. The recording medium may be specially designed and configured for the embodiment of the present invention, or may be known and used by a person skilled in the art of computer software. Examples of the computer-readable recording medium include hard disks, magnetic media such as floppy disks and magnetic tapes, optical recording media such as CD-ROMs and DVDs, magneto-optical media such as floppy disks, and ROMs, RAMs, flash memories, and the like. Hardware devices specially configured to store and execute the same program instructions are included. Examples of program instructions may include high-level language codes that can be executed by a computer using an interpreter or the like as well as machine language codes such as those generated by a compiler.

The above description is merely illustrative of the technical spirit of the present invention, and various modifications and variations will be possible without departing from the essential characteristics of the present invention by those skilled in the art to which the present invention pertains. Accordingly, the embodiments disclosed in the present invention are not intended to limit the technical spirit of the present invention, but to explain, and the scope of the technical spirit of the present invention is not limited by these embodiments. The protection scope of the present invention should be construed by the following claims, and all technical ideas within the scope equivalent thereto should be construed as being included in the scope of the present invention.

1: network
2: Synchronization Server
3: Multiple databases
21: synchronization unit
23: marker
25: update department
251: data acquisition unit
253: information delivery unit
255: data transfer unit
257: coincidence

Claims (13)

(a) when data change occurs in at least one database (hereinafter, the first database) among the multiple databases, synchronization is performed by replicating the changed data in one or more other databases (hereinafter, the second database) other than the first database step;
(b) displaying the changed data of the first database as specific information so that the changed data of the second database can be distinguished from the duplicate data of the second database; and
(c) updating other data that is inconsistent based on the data in which the specific information is displayed when the data corresponding to each other is inconsistent between the multiple databases;
A method for synchronizing multiple databases, including According to claim 1,
The step (b) is a method for synchronizing multiple databases, characterized in that the specific information is displayed in a tuple unit including change data. According to claim 1,
The step (c) is a method for synchronization of multiple databases, characterized in that when there are a plurality of data in which the specific information is displayed, other data that is inconsistent is updated based on the latest changed data (with reference to the timestamp). According to claim 1,
The step (c) is,
(c-1) obtaining comparison target data from one of the multiple databases (hereinafter, a third database);
(c-2) transmitting identification information on the obtained comparison target data from a third database to another database (hereinafter, referred to as a fourth database) of the multi-database;
(c-3) querying the comparison target data from the fourth database based on the identification information and transmitting the searched data to the third database; and
(c-4) When the comparison target data obtained from the fourth database and the comparison target data inconsistent are found after mutual comparison between the respective comparison target data among the total comparison target data obtained by collecting the comparison target data of the third database , updating and matching other comparison target data that do not match based on the comparison target data on which the specific information is displayed;
A method for synchronization of multiple databases comprising a. 5. The method of claim 4,
The method for synchronization of multiple databases, characterized in that the comparison target data is data in a tuple unit. Synchronization unit for performing synchronization by replicating the changed data in one or more other databases (hereinafter, second database) other than the first database when data change occurs in at least one database (hereinafter referred to as the first database) among the multiple databases ;
a marker for displaying the changed data of the first database as specific information to distinguish it from the duplicate data of the second database; and
an update unit configured to update other data that is inconsistent based on the data on which the specific information is displayed, when data discrepancy between the multiple databases occurs;
A device for synchronization of multiple databases comprising a. 7. The method of claim 6,
The apparatus for synchronization of multiple databases, characterized in that the marker displays the specific information in a tuple unit including change data. 7. The method of claim 6,
The apparatus for synchronization of multiple databases, characterized in that the update unit updates other data that is inconsistent based on the latest changed data when there are a plurality of pieces of data on which the specific information is displayed. 7. The method of claim 6,
The update unit,
a data acquisition unit for acquiring comparison target data from one of the multiple databases (hereinafter, a third database);
an information transfer unit configured to transmit identification information on the acquired comparison target data from a third database to another database (hereinafter, referred to as a fourth database) of the multi-database;
a data transfer unit for inquiring the corresponding comparison target data from the fourth database based on the identification information and transmitting the searched data to the third database; and
When the comparison target data obtained from the fourth database and the comparison target data obtained from the third database are compared with each other among the total comparison target data obtained by the collection of the comparison target data, when inconsistent comparison target data is found, the specific information is a matching unit for updating and matching other inconsistent comparison target data based on the displayed comparison target data;
Device for synchronization of multiple databases comprising a. 10. The method of claim 9,
The apparatus for synchronization of multiple databases, characterized in that the comparison target data is data in a tuple unit. A computer-readable recording medium recording a program for executing the method for synchronizing the multiple databases of any one of claims 1 to 5 on a computer. An application stored in a computer-readable recording medium in order to execute the method for synchronizing the multi-database according to any one of claims 1 to 5 in combination with hardware. A computer program stored in a computer-readable recording medium in order to execute the method for synchronizing the multi-database according to any one of claims 1 to 5 in a computer.

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