- 懒加载就是在查询过程中,返回resultMap中对应的collection或者association如果不需要第一时间使用所有记录的值,可以再后续使用到时再进行进一步的查询,减轻数据库查询负担,提高效率。
<select id="select" resultMap="scmuserResultMap">
select * from scmuser
</select>
<resultMap type="com.test.model.Scmuser" id="scmuserResultMap">
<id column="account" property="account"/>
<result column="name" property="name"/>
<result column="password" property="password"/>
<result column="createdate" property="createdate"/>
<result column="status" property="status"/>
<collection property="models" ofType="com.test.model.Usermodel" select="selectModelByAccount" column="account">
</collection>
</resultMap>
<select id="selectModelByAccount" parameterType="java.lang.String" resultType="com.test.model.Usermodel">
select
account,u.modelcode,s.modelname
from
usermodel u, systemmodel s
where
u.modelcode = s.modelcode
and
u.account = #{account}
</select>
<settings>
<setting name="lazyLoadingEnabled" value="true"/>
<setting name="aggressiveLazyLoading" value="false"/>
</settings>