Technique for replication of database

Abstract

Disclosed is a computer program stored in a computer readable storage medium, which includes encoded commands, wherein executing the computer program by one or more processors of a computer system allows the one or more processors to perform steps for change data capture (CDC) between a source database and a target database. The steps may include: a resource data acquisition step of acquiring resource data which is data obtained by monitoring a current resource of a source database server; a comparison information generation step of generating comparison information by comparing the resource data and a predetermined source database server load threshold value; a mode determination step of determining an operation mode of a changed data capture process which operates in the source database server based on the comparison information, the operation mode including a union mode and a division mode; and a mode changing step of changing the operation mode of the process to a mode determined in the mode determination step.

What is claims is: 
     
         1 . A non-transitory computer readable storage medium storing a computer program, which includes encoded commands, wherein executing the computer program by one or more processors of a computer system allows the one or more processors to change data capture (CDC) between a source database and a target database, the steps comprising:
 a resource data acquisition step of acquiring resource data which is data obtained by monitoring a current resource of a source database server;   a comparison information generation step of generating comparison information by comparing the resource data and a predetermined source database server load threshold value;   a mode determination step of determining an operation mode of a changed data capture process which operates in the source database server based on the comparison information, the operation mode including a union mode and a division mode; and   a mode changing step of changing the operation mode of the data capture process to a mode determined in the mode determination step.   
     
     
         2 . The non-transitory computer readable storage medium of  claim 1 , wherein the mode determination step includes
 determining the operation mode of the changed data capture process as the union mode when the resource data is less than the predetermined source database server load threshold value in the comparison information, and   determining the operation mode of the changed data capture process as the division mode when the resource data is equal to or more than the predetermined source database server load threshold value in the comparison information.   
     
     
         3 . The non-transitory computer readable storage medium of  claim 1 , further comprising:
 when the operation mode is changed to the union mode by the mode changing step of changing the operation mode of the data capture process to the mode determined in the mode determination step,   an extraction step of extracting, by the source database, changed information included in a record of a redo log of the source database;   an assembly step of analyzing a transaction for extracted changed information and reassembling associated transactions to generate changed data; and   a reflection step of completing commit of the changed data and reflecting a committed changed data to a target database.   
     
     
         4 . The non-transitory computer readable storage medium of  claim 3 , wherein a thread executing each step in each of the assembly step to the reflection step is processed by referring to a task queue, the task queue being at least a part of a memory storing the changed information and the changed data. 
     
     
         5 . The non-transitory computer readable storage medium of  claim 1 , further comprising:
 when the operation mode is changed to the division mode by the mode changing step of changing the operation mode of the process to the mode determined in the mode determination step,   an extraction step of extracting, by the source database, changed information included in a record of a redo log of the source database; and   a transmission step of generating, by a target database server, the changed data by reassembling transactions for the changed information and transmitting the changed information to the target database so as to reflect committed changed data to the target database.   
     
     
         6 . The non-transitory computer readable storage medium of  claim 1 , wherein in the mode changing step, a mode change is executed when a task queue is empty. 
     
     
         7 . The non-transitory computer readable storage medium of  claim 1 , wherein the resource data acquisition step is a step of acquiring resource data which is data obtained by monitoring at least one resource of a CPU usage, a memory available capacity, and an input/output load of the source database server. 
     
     
         8 . A server comprising one or more processors for performing change data capture (CDC) between a source database and a target database, the one or more processors implement:
 a resource data acquisition module acquiring resource data which is data obtained by monitoring a current resource of a source database server;   a comparison information generation module generating comparison information by comparing the resource data and a predetermined source database server load threshold value; and   a control module determining an operation mode of a changed data capture process which operates in the source database server based on the comparison information, the operation mode including a union mode and a division mode, and changing an operation mode of the process to a determined operation mode.   
     
     
         9 . A method for performing change data capture (CDC) between a source database and a target database, the method comprising:
 a resource data acquisition step of acquiring resource data which is data obtained by monitoring a current resource of a source database server;   a comparison information generation step of generating comparison information by comparing the resource data and a predetermined source database server load threshold value;   a mode determination step of determining an operation mode of a changed data capture process which operates in the source database server based on the comparison information, the operation mode including a union mode and a division mode; and   a mode changing step of changing the operation mode of the data capture process to a mode determined in the mode determination step.