方法一:
insert id="insert" parameterType="Person" useGeneratedKeys="true" keyProperty="id">
insert into person(name,pswd) values(#{name},#{pswd})
</insert>
方法二:
<insert id="insert" parameterType="Person">
<selectKey keyProperty="id" resultType="long">
select LAST_INSERT_ID()
</selectKey>
insert into person(name,pswd) values(#{name},#{pswd})
</insert>