This period of self-study hadoop, met a topic, posted a look at how to achieve!
A user tables in MySQL, table structure as follows
Id name
1 zhangsan
2 lisi
3 wangwu


HDFS has a transaction log tables, log following structure
1 12
24
22 12
3 45

-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
Requirements: results form the following
Zhagnsan 12
Lisi 36
Wangwu 45