//基于注解
@Mapper
public interface reboudapt {

    @Select("select * from dept")
    List<dept> huoqudept();

    //删除语句
    @Delete("delete  from dept where id = #{id}")
    void deletesc(Integer id);

    //增加语句
    @Insert("insert into dept(name, create_time, update_time) values ( #{name},#{createTime}, #{updateTime})")
    void add(dept posT);

    //查询语句
    @Select("select *from dept where id = #{id}")
    dept getcha(@Param("id") Integer id);

    //修改语句
    @Update("update dept set  name = #{name} , create_time = #{createTime} , update_time = #{updateTime} where id = #{id}")
    void setsc(dept xiugai);
    
}

//基于xml文件

<!--专门的文档声名-->
<?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.example.tlias.mapperclass.rebouemp">
    
<!--修改语句-->
    <update id="update">
        update emp
        <set>
            <if test="username != null and username != ''">
                username = #{username},
            </if>
            <if test="password != null and password != ''">
                password = #{password},
            </if>
            <if test="name != null and name != ''">
                name = #{name},
            </if>
            <if test="gender != null">
                gender = #{gender},
            </if>
            <if test="image != null and image != ''">
                image = #{image},
            </if>
            <if test="job != null">
                job = #{job},
            </if>
            <if test="entrydate != null">
                entrydate = #{entrydate},
            </if>
                dept_id = #{deptId},
            <if test="updateTime != null">
                update_time = #{updateTime}
            </if>
        </set>
        where id = #{id}
    </update>
    
    <!--删除语句-->
    <delete id="deletebs">
        delete from emp where id in
        <foreach collection="ids" item="id" separator="," open="(" close=")">
            #{id}
        </foreach>
    </delete>
    
    <!--查询语句-->
    <select id="fongzhuang" resultType="com.example.tlias.Resource.emp">
        select * from emp
        <where>
            <if test=" name != null">
                name like concat('%' ,#{name},'%')
            </if>
            <if test="gender != null">
                and gender = #{gender}
            </if>
            <if test="begin != null and  end != null ">
                and entrydate between #{begin} and #{end}
            </if>
        </where>
    </select>

</mapper>

//xml文件配置需要同包同名放在resources资源文件下