Patents - 11880386

11,880,386 - Method and system for using before images of replicated changes from a source database with current target database images read from the target database when continuously comparing two databases which are actively being kept synchronized

An automated method and system are provided for comparing a source database and a target database that are intended to be kept in synchronization with each other. An application processes transactions that are posted to the source database and replicated to the target database. Before images of changes made to records or rows of the source database resulting from transactions posted to the source database into a first change log are collected. The before images of changes made to records or rows of the source database are replicated to the target database. Current images of records or rows of the target database that correspond to the before images of changes made to records or rows of the source database are read. Representations of the before images of changes made to records or rows of the source database are compared with representations of the current images of records or rows of the target database that correspond to the before images of changes made to records or rows of the source database. A corrective action is performed when the comparison indicates that the representations of the before images of changes made to records or rows of the source database do not match the representations of the current images of records or rows of the target database that correspond to the before images of changes made to records or rows of the source database.