(Turn) to solve mybatis of mapper.xml no data query, the result has been a problem for the null

Background: Record mybatis use related problems encountered in the process.

Mybatis not solve the mapper.xml query data, the result has been a problem for the null

solution:

1 modified entity class with the same name of the database field

2 Modify the sql query, surnamed

3 mybatis in turn camelCasing

4 using resultMap tag (3 and 4 is not compatible)