mybatis project 一对多 分步查询提交

mybatis_train/src/main/java/com/mapper/AccountMapper.java

@@ -13,7 +13,7 @@ public interface AccountMapper {
     List<AccountEntity> findAll(Integer id);
     void updateOne(AccountEntity accountEntity);
     void insertOne(AccountEntity accountEntity);
-    AccountRealEntity findByResultMap();
+    AccountRealEntity findByDepId(Integer depId);
     // 多对一查询
     AccountVO findVO(Integer id);
     AccountVO findByStep(Integer id);

mybatis_train/src/main/java/com/mapper/DepartmentMapper.java

@@ -8,4 +8,7 @@ public interface DepartmentMapper {
     // 一对多查询
     DepartmentVO oneFindMore(Integer id);
     DepartmentEntity findById(Integer depId);
+    // 一对多分步查询
+    DepartmentVO findByStep(Integer id);
+
 }

mybatis_train/src/main/resources/com/mapper/AccountMapper.xml

@@ -25,11 +25,10 @@
         <result property="depId" column="dep_id"></result>
         <association property="departmentEntity"
             select="com.mapper.DepartmentMapper.findById"
-                     column="dep_id"
+            column="dep_id"
         ></association>
     </resultMap>
-    
-    
+
     <select id="findAll" resultType="account"
             parameterType="java.lang.Integer"
     >
@@ -41,8 +40,8 @@
     <update id="updateOne" parameterType="account">
         update account set user_name= #{user_name},balance=#{balance} where id = #{id}
     </update>
-    <select id="findByResultMap" resultType="com.pojo.entity.AccountRealEntity">
-        select * from account where id = 3
+    <select id="findByDepId" resultType="com.pojo.entity.AccountRealEntity">
+        select * from account where dep_id = #{dep_id}
     </select>
     <select id="findVO" resultMap="voMap" parameterType="java.lang.Integer">
         select a.*,b.dep_name from account a left join department b on a.dep_id = b.dep_id

mybatis_train/src/main/resources/com/mapper/DepartmentMapper.xml

@@ -13,10 +13,24 @@
             <result property="depId" column="dep_id"></result>
         </collection>
     </resultMap>
+    <resultMap id="findByStep" type="com.pojo.dto.DepartmentVO">
+        <id property="depId" column="dep_id"></id>
+        <result property="depName" column="dep_name"></result>
+        <collection property="accountEntities"
+                    select="com.mapper.AccountMapper.findByDepId"
+                    column="dep_id">
+        </collection>
+    </resultMap>
+
 
     <select id="findById" parameterType="java.lang.Integer" resultType="com.pojo.entity.DepartmentEntity">
         select * from department where dep_id = #{depId}
     </select>
+
+    <select id="findByStep" parameterType="java.lang.Integer" resultMap="findByStep">
+        select * from department where dep_id = #{depId}
+    </select>
+
     <select id="oneFindMore" parameterType="java.lang.Integer" resultMap="oneMore">
         select a.*,b.* from department a left join account b on a.dep_id = b.dep_id
         where a.dep_id = #{id1}

mybatis_train/src/main/resources/mybatisConfig.xml

@@ -7,6 +7,7 @@
     <settings>
         <setting name="logImpl" value="LOG4J2"/>
         <setting name="mapUnderscoreToCamelCase" value="true"/>
+        <setting name="lazyLoadingEnabled" value="true"/>
     </settings>
     <!--    Mapper文件注册-->
     <typeAliases>

mybatis_train/src/test/java/Test1.java

@@ -51,6 +51,6 @@ public class Test1 {
         SqlSessionFactory sqlSessionFactoryBuilder = new SqlSessionFactoryBuilder().build(resourceAsStream);
         SqlSession sqlSession = sqlSessionFactoryBuilder.openSession(true);
         AccountMapper mapper = sqlSession.getMapper(AccountMapper.class);
-        AccountRealEntity byResultMap = mapper.findByResultMap();
+//        AccountRealEntity byResultMap = mapper.findByResultMap();
     }
 }

mybatis_train/src/test/java/Test3.java

@@ -82,6 +82,8 @@ public class Test3 {
     @Test
     public void testFindStep() {
         AccountVO byStep = accountMapper.findByStep(16);
+        System.out.println(byStep.getUserName());
+        return;
     }
 
 

mybatis_train/src/test/java/TestResultMap.java

@@ -30,8 +30,21 @@ public class TestResultMap {
     public void resultMap1() {
         AccountVO vo = accountMapper.findVO(16);
     }
+
+    /**
+     * 测试一对多
+     */
     @Test
     public void findOneMore() {
         DepartmentVO departmentVO = departmentMapper.oneFindMore(1);
     }
+    /**
+     * 测试一对多 分步
+     *
+     */
+    @Test
+    public void findOneByStep() {
+        DepartmentVO byStep = departmentMapper.findByStep(1);
+        System.out.println(byStep.getDepName());
+    }
 }