MapReduce: A Minor Step Forward

An execution engine that runs on multi-thousand node clusters really is an important step forward. The separation of execution engine and storage engine into extensible parts isn’t innovative but it is a very flexible approach that current generation commercial RDBMS could profit from. MapReduce最突出的地方就是这是一个通用的计算引擎,并且非常具有扩展性。将存储引擎和执行引擎分离,值得RDBMS学习和借鉴

1. MapReduce is a step backwards in database access

2. MapReduce is a poor implementation

3. MapReduce is not novel

4. MapReduce is missing features

5. MapReduce is incompatible with the DBMS tools