Mycat2
MySQL Proxy using Java NIO based on Sharding SQL, Calcite
...Custom Calcite distributed query engine, edit SQL to relationship algebra expression, rule optimization engine, and cost optimization engine, generate physical execution plan, support logic view. Any cross-currant cross-table join query, support cross-currant cross-table non-associated query, support cross-currant cross-table association query, support cross-currant cross-table Window grammar, support global secondary index, limited support storage process, support visualization configuration. Support parallel extraction of result sets, support the automatic transfer of back-end result sets, support multiple routing notes, and optimizer notes. ...