Research of Log-based Change Data Capture
CDC(Change data capture) is a strategic component in the data integration infrastructure and compliments other technologies such ETL(Extract-Transform-Load) and EAI(Enterprise Application Integration).Many companies have home-grown CDC solutions that are typically limited in scope and are costly and difficult to maintain.By scanning the transactions log files one can capture the changes,but most database systems do not provide internal format of their log files.However few databases like Oracle,SQL Server and DB2 provide a programmed library to interface with their transaction log files.Some of these API(Application Program Interface) can read active redo logs,some read redo logs,and some read archive logs.In some cases it is difficult to ensure the reliability of reading log files.Existing researches are how to read log records by using API but ignore the analysis of reliability.We considered the reliability conditions of reading different log files and propose the algorithm of reading log records.And the algorithm is proposed to efficiently extract change data.The experiment shows the analysis model.