Mybatis 中的一对一,一对多,多对多的配置原则示例代码
作者:manleo0527
这篇文章主要介绍了 Mybatis 中的一对一,一对多,多对多的配置原则示例代码,需要的朋友可以参考下
什么是 MyBatis ?
MyBatis 是支持定制化 SQL、存储过程以及高级映射的优秀的持久层框架。MyBatis 避免了几乎所有的 JDBC 代码和手动设置参数以及获取结果集。MyBatis 可以对配置和原生Map使用简单的 XML 或注解,将接口和 Java 的 POJOs(Plain Old Java Objects,普通的 Java对象)映射成数据库中的记录。
表:market_plan(营销计划(关联了用户))
market_plan_product(产品关联营销计划)
market_plan_label(标签关联营销计划)
market_plan_ideadata(创意素材关联营销计划)
user_ideadata_activity(活动关联用户,活动关联创意素材表)
user(用户表)
配置原则:A关联B,将A的resultMap关联(association)到B的resultMap中,这样才能在写关联查询sql语句的时候,查询出A,B表中的属性。多张表的关联也是一样的道理!
配置xml示例:
<resultMap id="userResultMap" type="com.mchuan.fastmarketplat.b.entity.User"> <id column="USER_ID" property="id" /> <result column="ACCOUNT" property="account" /> <result column="NAME" property="name" /> <result column="MOBILE" property="mobile" /> </resultMap> <resultMap id="labelResultMap" type="com.mchuan.fastmarketplat.b.entity.MarketPlanLabel"> <id property="id" column="LABEL_ID" /> <result property="gender" column="GENDER" /> <result property="area" column="AREA" /> <result property="age" column="AGE" /> <result property="deviceType" column="DEVICE_TYPE" /> <result property="communicationFee" column="COMMUNICATION_FEE" /> <result property="actionLabels" column="ACTION_LABELS" /> <result property="netScene" column="NET_SCENE" /> </resultMap> <resultMap id="productResultMap" type="com.mchuan.fastmarketplat.b.entity.MarketPlanProduct"> <id property="id" column="PRODUCT_ID" /> <result property="coverAmount" column="COVER_AMOUNT" /> </resultMap> <resultMap id="activityResultMap" type="com.mchuan.fastmarketplat.b.entity.UserActivity"> <id column="AC_ID" property="id" /> <result column="ACTIVITY_ID" property="activityId" jdbcType="INTEGER" /> <result column="COVER_URL" property="coverUrl" jdbcType="VARCHAR" /> <result column="ACTIVITY_URL" property="activityUrl" jdbcType="VARCHAR" /> <result column="VIEW_URL" property="viewUrl" jdbcType="VARCHAR" /> <result column="CREATE_TIME" property="createTime" /> <result column="UPDATE_TIME" property="updateTime" /> </resultMap> <resultMap id="ideaDataResultMap" type="com.mchuan.fastmarketplat.b.entity.MarketPlanIdeaData"> <id property="id" column="IDEA_DATA_ID" /> <result property="content" column="CONTENT" /> <result property="linkUrl" column="LINK_URL" /> <!-- ideaData关联属性 --> <association property="userActivity" javaType="com.mchuan.fastmarketplat.b.entity.UserActivity" resultMap="activityResultMap" /> </resultMap> <resultMap id="BaseResultMap" type="com.mchuan.fastmarketplat.b.entity.MarketPlan"> <id column="ID" property="id" jdbcType="INTEGER" /> <result column="PLAN_NAME" property="planName" jdbcType="VARCHAR" /> <result column="BUDGET" property="budget" jdbcType="DECIMAL" /> <result column="ACTUAL_BUDGET" property="actualBudget" jdbcType="DECIMAL" /> <result column="DEMAND_TYPE" property="demandType" jdbcType="VARCHAR" /> <result column="START_DATE" property="startDate" /> <result column="END_DATE" property="endDate" /> <result column="CREATE_STATUS" property="createStatus" jdbcType="INTEGER" /> <result column="CREATE_TIME" property="createTime" /> <result column="UPDATE_TIME" property="updateTime" /> <result column="NOTE" property="note" jdbcType="VARCHAR" /> <result column="STATUS" property="status" jdbcType="INTEGER" /> <result column="DESTPAGE_URL" property="destpageUrl" jdbcType="VARCHAR" /> <result column="IS_AWARD" property="isAward" jdbcType="INTEGER" /> <result column="AWARD_MONEY" property="awardMoney" jdbcType="DECIMAL" /> <result column="ADVERTISER" property="advertiser" jdbcType="VARCHAR" /> <result column="INDUSTRY" property="industry" jdbcType="INTEGER" />
<!-- marketPlan关联属性 --> <association property="user" javaType="com.mchuan.fastmarketplat.b.entity.User" resultMap="userResultMap" /> <association property="marketPlanLabel" javaType="com.mchuan.fastmarketplat.b.entity.MarketPlanLabel" resultMap="labelResultMap" /> <association property="marketPlanProduct" javaType="com.mchuan.fastmarketplat.b.entity.MarketPlanProduct" resultMap="productResultMap" /> <association property="marketPlanIdeaData" javaType="com.mchuan.fastmarketplat.b.entity.MarketPlanIdeaData" resultMap="ideaDataResultMap" /> </resultMap>
以上所述是小编给大家介绍的 Mybatis 中的一对一,一对多,多对多的配置原则示例代码,希望对大家有所帮助,如果大家有任何疑问请给我留言,小编会及时回复大家的。在此也非常感谢大家对脚本之家网站的支持!