1,在进行统计查询时候,不想写映射的实体类,这时候设置返回的resultType类型是map <select id="getMap" resultType="java.util.Map" parameterType="java.util.Map" > select count(*) as totalTimes ,sum(brushLong) as totalSecond from xxxx where toothId = #{toot
创建一个Student.java类:该类需要一个无参的构造函数,以及属性的get/set方法 public class Student implements Serializable { private static final long serialVersionUID = 2257468553009291835L; private int id; private String name; private int age; public Student() { } public Student