ExecutorException: Statement returned more than one row, where no more than one was expected.

Use Mybatis This error occurs when ：

Cause: org.apache.ibatis.executor.ExecutorException: Statement returned more than one row, where no more than one was expected.

Translated into Chinese ： Statement returned multiple lines , No more than one line is expected .
People words ： Some sql The statement should have found a piece of data , The result returned multiple pieces of data

Error causes and Solutions ：

1. Look at your dao layer SQL Whether there is a logical error in the statement ： For example, many to one 、 One to many hours select Whether the following fully qualified method name points to an error .
2. In itself SQL Whether there is a logical error in the statement