mybatis中一些常用的增删改查操作

①查询出所有的记录
 List<Player> selectAll();

<select id="selectAll" resultType="Player">
        select * from Player
    </select>

②根据主键查询
Player selectById(Integer id);

<select id="selectById" parameterType="Integer" resultType="Player">
        select * from Player where id=#{id}
    </select>

③修改
int update(Player player);

 <update id="update" parameterType="Player">
        update Player set name=#{name},city=#{city} where id=#{id}
    </update>

④根据主键删除
int deleteById(Integer id);

<delete id="deleteById">
        delete from Player where id=#{id}
    </delete>

⑤增加
int insert(Player player);

   <insert id="insert" parameterType="Player">
         <selectKey keyProperty="id" order="BEFORE" resultType="integer">
               select seq_play.nextval from dual
         </selectKey>
        insert into Player(id,name,city) values(#{id},#{name},#{city})
    </insert>

⑥查询出所有字段（orderColumn：指定排序列）
List<Player> selectAlls(String orderColumn);

<select id="selectAlls" resultType="Player">
        select * from Player order by ${value}
    </select>

⑦根据id或name查找数据，演示多个参数的取值方式，通过@param取别名
List<Player> selectByIdOrName(@Param("id") Integer id,@Param("name") String name,@Param("city") String city);

<select id="selectByIdOrName" resultType="Player">
        select * from Player
        <where>
            <choose>
                <when test="id!=null">
                    id=#{id}
                </when>
                <when test="name!=null">
                    name=#{name}
                </when>
                <otherwise>
                    city=#{city}
                </otherwise>
            </choose>
        </where>
    </select>

⑧参数传递的是map时，#{key}取value
List<Player> selectMap(Map<String,Object> map);

<select id="selectMap" parameterType="java.util.Map" resultType="Player">
        select * from Player
        <where>
            <if test="id!=null">
                id=#{id}
            </if>
            <if test="name!=null and name!=''">
                or name=#{name}
            </if>
            <if test="city!=null">
                or city=#{city}
            </if>
        </where>
    </select>

⑨批量删除 传递数组/集合
int deleteByIds(Integer[] ids);

 <delete id="deleteByIds">
        delete from Player where id in
        <foreach collection="array" item="id" open="(" close=")" separator=",">
            #{id}
        </foreach>
    </delete>

⑩批量插入
int batchInsert(List<Player>playerList);

<insert id="batchInsert" parameterType="java.util.List">
        begin
        <foreach collection="list" item="player">
            insert into Player(id,name,city) values (seq_play.nextval,#{player.name},#{player.city});
        </foreach>
        commit ;
        end;
    </insert>

11、选择性更新
int updateSelective(Player player);

<update id="updateSelective" parameterType="Player">
        update Player
        <set>
            <if test="name!=null">
                name=#{name},
            </if>
            <if test="city!=null">
                city=#{city}
            </if>
        </set>
        where id=#{id}
    </update>

12、选择性插入数据
int insertSelective(Player player);

<insert id="insertSelective" parameterType="Player">
        <selectKey keyProperty="id" resultType="integer" order="BEFORE">
             select seq_play.nextval from dual
        </selectKey>
        insert into Player
        <trim prefix="(" suffix=")" suffixOverrides=",">
            id,
            <if test="name!=null">name,</if>
            <if test="city!=null">city</if>
        </trim>
        <trim prefix="values (" suffix=")" suffixOverrides=",">
            #{id},
            <if test="name!=null">#{name},</if>
            <if test="city!=null">#{city}</if>
        </trim>
    </insert>

13、根据名称进行模糊查询
List<Player> selectByName(@Param("name") String name);

<select id="selectByName" resultType="Player">
        <bind name="nameLike" value="'%'+name+'%'"/>
        select * from Player where name like #{nameLike}
    </select>

以下为上面方法的测试，仅供参考

@Test
    public void test() throws IOException {
        InputStream is= Resources.getResourceAsStream("mybatis.xml");
        SqlSessionFactory sqlSessionFactory=new SqlSessionFactoryBuilder().build(is);
        SqlSession sqlSession=sqlSessionFactory.openSession();
        PlayerMapper mapper=sqlSession.getMapper(PlayerMapper.class);
        System.out.println("==========查询所有的记录===========");
        List<Player> playerList=mapper.selectAll();
        for (Player player:playerList){
            System.out.println(player);
        }
        System.out.println("==========根据主键查询记录=============");
        Player player = mapper.selectById(2);
        System.out.println(player);
        System.out.println("=============修改记录=============");
        player.setName("汤普森");
        player.setCity("金州勇士");
        int update = mapper.update(player);
        System.out.println(update);
        System.out.println("============根据主键删除============");
        int i = mapper.deleteById(4);
        System.out.println(i);
        System.out.println("============插入数据===========");
        //Player player1=new Player("一哥","金州勇士");
        //int i1 = mapper.insert(player1);
        //System.out.println(i1);
        System.out.println("===========根据指定序列查找所有字段================");
        List<Player> playerList1 = mapper.selectAlls("id");
        for (Player player2:playerList1){
            System.out.println(player2);
        }
        System.out.println("==========根据id或name查找数据===============");
        List<Player> playerList2 = mapper.selectByIdOrName(1, "乔丹", "芝加哥");
        for (Player player2:playerList2){
            System.out.println(playerList2);
        }
        List<Player> playerList3 = mapper.selectByIdOrName(null, null, "金州勇士");
        for (Player player2:playerList3){
            System.out.println(playerList3);
        }
        System.out.println("============测试传递map============");
        HashMap<String,Object> map=new HashMap<>();
        map.put("id",3);
        map.put("name","科比");
        map.put("city","洛杉矶");
        List<Player> playerList4 = mapper.selectMap(map);
        for (Player player2:playerList4){
            System.out.println(player2);
        }
        System.out.println("=========批量删除===========");
        int i1 = mapper.deleteByIds(new Integer[]{13,15});
        System.out.println(i1);
        System.out.println("==========批量增加===========");
        //List<Player> playerList5= Arrays.asList(
                //new Player("字母哥","快船"),
                //new Player("麦迪","火箭"),
                //new Player("哈登","火箭")
        //);
        //int i2 = mapper.batchInsert(playerList5);
        //System.out.println(i2);
        System.out.println("=========选择性更新===========");
        Player player1=mapper.selectById(2);
        player1.setName("库里");
        player1.setCity("金州幼儿园");
        int i2 = mapper.updateSelective(player1);
        System.out.println(i2);
        Player player2=mapper.selectById(18);
        player2.setName("库里");
        player2.setCity(null);
        int i3 = mapper.updateSelective(player2);
        System.out.println(i3);
        System.out.println("==========选择性增加数据==========");
        Player player3=new Player();
        player3.setName(null);
        player3.setCity("猛龙");
        int i4 = mapper.insertSelective(player3);
        System.out.println(i4);
        Player player4=new Player();
        player4.setName("奥尼尔");
        player4.setCity(null);
        int i5 = mapper.insertSelective(player4);
        System.out.println(i5);
        System.out.println("=========根据名字模糊查询==========");
        String name="母";
        List<Player> playerList5 = mapper.selectByName(name);
        for (Player player5:playerList5){
            System.out.println(player5);
        }


        sqlSession.commit();
        sqlSession.close();
        is.close();
    }