mybatis mapper写法 Mybatis增删改查mapper文件写法详解
real_孟林洁 人气:0想了解Mybatis增删改查mapper文件写法详解的相关内容吗,real_孟林洁在本文为您仔细讲解mybatis mapper写法的相关知识和一些Code实例,欢迎阅读和指正,我们先划重点:mybatis,mapper写法,下面大家一起来学习吧。
1. 插入
<mapper namespace="需要实现接口的全类名"> <insert id="需要实现的接口里的方法名" parameterType="方法参数类型,如果是对象要写全类名"> INSERT sql命令(命令里通过#{}获取对象属性) <!--注意属性名区分大小写 --> </insert> <mapper>
EG:
<mapper namespace="com.mlj.dao.PersonDao"> <insert id="insertPerson" parameterType="com.mlj.entity.Prac_Person"> INSERT INTO PRAC_PERSON(p_NAME,P_PASSWORD) VALUES(#{name},#{password}) </insert> </mapper>
2. 查询
<select id="方法名" parameterType="方法参数类型" resultType="方法返回值类型,全类名"> SELECT 表里字段名 AS 结果字段名 FROM 表名 WHERE 条件 <!--注意:结果字段名与属性名保持一致,区分大小写--> </select>
EG:
<resultMap type="Address" id="address"> <result column="A_PERSON" property="personId"/> <result column="A_ADDRESS" property="address"/> <result column="A_NUMBER" property="number"/></resultMap> <select id="selectAddressByPersonId" parameterType="java.lang.String" resultMap="address"> SELECT * FROM PRAC_ADDRESS LEFT JOIN PRAC_PERSON ON A_PERSON=#{personId} AND PRAC_ADDRESS.A_PERSON=PRAC_PERSON.P_ID </select>
此处先配置resultMapp,使表列名与属性名一致。
3.修改
与前面插入除了sql语句基本一致,直接贴代码
<update id="updatePersonInformation" parameterType="com.mlj.entity.Prac_Person" > UPDATE PRAC_PERSON SET P_NAME=#{name},P_PASSWORD=#{password} WHERE P_ID=#{id} <!-- 属性字段名区分大小写 --> </update>
4.删除
与前面插入除了sql语句基本一致,直接贴代码
<delete id="deletePerson" parameterType="java.lang.Integer"> DELETE FROM PRAC_PERSON WHERE P_ID=#{id} </delete>
下面看下mybatis的mapper配置文件的一般写法
mapper.xml大致如下:
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd"> <mapper namespace="com.hzcominfo.voucher.CommodityCategoryManager"> <cache-ref namespace="com.hzcominfo.dataggr.cloud" /> <insert id="insertCommodityCategoryManager" parameterType="com.hzcominfo.voucher.mapper.CommodityCategoryManager" keyProperty="id" > INSERT INTO COMMODITY_CATEGORY_MANAGER ( <include refid="fields" /> ) VALUES ( <include refid="values" /> ) </insert> <update id="updateCommodityCategoryManager" parameterType="com.hzcominfo.voucher.mapper.CommodityCategoryManagerKey"> UPDATE COMMODITY_CATEGORY_MANAGER <include refid="set" /> <include refid="where" /> </update> <update id="deleteCommodityCategoryManager" parameterType="com.hzcominfo.voucher.mapper.CommodityCategoryManagerKey"> DELETE FROM COMMODITY_CATEGORY_MANAGER <include refid="where" /> </update> <select id="selectCommodityCategoryManager" parameterType="String" resultType="com.hzcominfo.voucher.mapper.CommodityCategoryManager"> SELECT * FROM COMMODITY_CATEGORY_MANAGER <include refid="where" /> </select> <select id="selectCommodityCategoryManagerByCriteria" parameterType="net.butfly.albacore.dbo.criteria.Criteria" resultType="com.hzcominfo.voucher.mapper.CommodityCategoryManagerKey"> SELECT CATEGORY_ID, USER_ID FROM COMMODITY_CATEGORY_MANAGER <include refid="where" /> </select> <select id="countCommodityCategoryManagerByCriteria" parameterType="net.butfly.albacore.dbo.criteria.Criteria" resultType="long"> SELECT count(*) FROM COMMODITY_CATEGORY_MANAGER <include refid="where" /> </select> <sql id="fields"> <if test="categoryId!=null">CATEGORY_ID</if> <if test="userId!=null">,USER_ID</if> </sql> <sql id="values"> <if test="categoryId!=null">#{categoryId}</if> <if test="userId!=null">,#{userId}</if> </sql> <sql id="set"> <set> <trim prefix="" prefixOverrides=","> <if test="categoryId!=null">,CATEGORY_ID=#{categoryId}</if> <if test="userId!=null">,USER_ID=#{userId}</if> </trim> </set> </sql> <sql id="where"> <where> <trim prefix="" prefixOverrides="and|or" > <if test="categoryId!=null">AND CATEGORY_ID=#{categoryId}</if> <if test="userId!=null">AND USER_ID=#{userId}</if> </trim> </where> </sql> </mapper>
以上所述是小编给大家介绍的Mybatis增删改查mapper文件写法,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网站的支持!
加载全部内容