TECHNIQUE FOR DUPLEXING DATABASE

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.