主键不自增:返回值是插入的条数
<insert id="add" parameterType="EStudent">
insert into TStudent(name, age) values(#{name}, #{age})
</insert
主键自增:
<insert id="add" parameterType="EStudent" useGeneratedKeys="true" keyProperty="id">
insert into TStudent(name, age) values(#{name}, #{age})
</insert>