In general, the read-write separation technology can solve some of the problems on mismatch between read and write in the current big data environment, but most of the current read-write separation technology are prepared for homogeneous database. Due to the inconsistent storage structure, heterogeneous distributed database systems composed of a row storage database and a columnar storage database will face many difficulties like format conversion and mismatch of synchronization speed in data synchronization compared to a homogeneous distributed database system. This study proposes the use of MySQL binary log to perform the TD-Reduction of SQL. It designs and implements Binlog parser BinParser and Binlog restorer BinReducer, which based on the mixed format. Different events perform log parsing and restoring according to the corresponding rules to generate executable SQL statements. Based on the above techniques, this study has implemented Cynomys, a distributed database data synchronization tool. In the experimental environment, Cynomys has shown sound performance. The method is suitable for data synchronization between all other heterogeneous databases with a similar mechanism like Binlog.