Mybatis--模糊查询--分页查询--动态sql语句

最新推荐文章于 2024-03-15 11:22:11 发布

Eiffel_Wu

最新推荐文章于 2024-03-15 11:22:11 发布

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分类专栏： SSM 文章标签： mybatis模糊查询 mybatis分页查询 mybatis动态sql语句

本文链接：https://blog.youkuaiyun.com/Eiffel_Wu/article/details/100676094

Mybatis学习02

一、模糊查询

1、mapper接口层

package com.java.mapper;

import com.java.model.EmpEntity;

import java.util.List;
import java.util.Map;

public interface EmpMapper {
   
   

    /**
     * 参数为String类型的模糊查询
     * @param name
     * @return
     */
    List<EmpEntity> selectLikeName(String name);

    /**
     * 参数为实体类对象的模糊查询
     * @param emp
     * @return
     */
    List<EmpEntity> selectLikeEmpName(EmpEntity emp);

    /**
     * 参数为map集合的模糊查询
     * @param map
     * @return
     */
    List<EmpEntity> selectLikeEmpNameMap(Map map);

}

2、映射文件：xxxMapper.xml

<?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">
<!--代理扫描  namespace属性表示当前代理的命名空间，属性值为mapper接口地址,相当于mapper接口实现类 -->
<mapper namespace="com.java.mapper.EmpMapper">
    
    <!--要查询的sql字段-->
    <sql id="empSQL">
        number,name,job,mgr,hiredate,sal,comm,deptno
    </sql>

    <!--1、参数为String类型的模糊查询-->
    <!--方法1-->
    <select id="selectLikeName" parameterType="string" resultType="EmpEntity">
        SELECT <include refid="empSQL"/> FROM emp WHERE name LIKE "%"#{name}"%"
    </select>

    <!--方法2：推荐使用-->
    <select id="selectLikeName" parameterType="string" resultType="EmpEntity">
        SELECT <include refid="empSQL"/> FROM emp WHERE name LIKE concat("%",#{name},"%")
    </select>

    <!--方法3，SQL语句：SELECT number,name,job,mgr,hiredate,sal,comm,deptno FROM emp WHERE name LIKE "%子%" -->
    <select id="selectLikeName" parameterType="string" resultType="EmpEntity">
        SELECT <include refid="empSQL"/> FROM emp WHERE name LIKE "%${value}%"
    </select>


    <!--2、参数为实体类对象的模糊查询-->
    <!--方法1-->
    <select id="selectLikeEmpName" parameterType="EmpEntity" resultType="EmpEntity">
        SELECT <include refid="empSQL"/> FROM emp WHERE name LIKE concat("%",#{name},"%")
    </select>

    <!--方法2-->
    <select id="selectLikeEmpName" parameterType="EmpEntity" resultType="EmpEntity">
        SELECT <include refid="empSQL"/> FROM emp WHERE name LIKE "%"#{name}"%"
    </select>

    <!--方法3-->
    <select id="selectLikeEmpName" parameterType="EmpEntity" resultType="EmpEntity">
        SELECT <include refid="empSQL"/> FROM emp WHERE name LIKE '%${name}%'
    </select>
    

    <!--3、参数为map集合的模糊查询，#{}中参数为map的key值-->
    <select id="selectLikeEmpNameMap" parameterType="map" resultType="EmpEntity">
        SELECT <include refid="empSQL"/> FROM emp WHERE name LIKE "%"#{name}"%"
    </select>
</mapper>

3、测试类

package com.java;

import com.java.mapper.EmpMapper;
import com.java.model.EmpEntity;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;

import java.io.IOException;
import java.io.InputStream;
import java.util.HashMap;

/**
 * @author Liushun
 * @date Created in 2018/10/4 21:36
 * @description
 */
public class EmpTest {
   
   

    private SqlSession sqlSession = null;

    @Before
    public void init() throws IOException {
   
   
        // 1、加载核心配置文件sqlMapConfig.xml
        InputStream is = Resources.getResourceAsStream("sqlMapConfig.xml");
        // 2、创建sqlSessionFactory会话工厂
        SqlSessionFactoryBuilder builder = new SqlSessionFac