<delete id="delete" parameterType="java.lang.Integer">
         delete from cm_news where id=#{id}

<a name="Mp61e"></a>
# 3.多个关键词模糊查询
```xml
<select id="datalistPage" parameterType="page" resultType="pd">
   select
   <include refid="Field"></include>
   from 
   <include refid="tableName"></include>
   where 1=1
   <if test="pd.keywords!= null and pd.keywords != ''"><!-- 关键词检索 -->
      and(
                 BOOK_NAME LIKE CONCAT('%',#{pd.keywords},'%')
               OR  BOOK_AUTHO LIKE CONCAT('%',#{pd.keywords},'%')
               OR  BOOK_TYPE LIKE CONCAT('%',#{pd.keywords},'%')
               OR  BOOK_PRESS LIKE CONCAT('%',#{pd.keywords},'%')
               OR  BOOK_NUM LIKE CONCAT('%',#{pd.keywords},'%')
      )
   </if>
</select>

4.多表关联查询

<select id="getOperationLogsPage" resultType="com.pactera.crm.dto.OperationLogDto">
    select
    a.operation_log_id as operationLogId,
    a.operation_detail as operationDetail,
    a.user_id as userId,
    a.operation_time as operationTime,
    a.operation_module as operationModule,
    a.create_at as createAt,
    a.update_at as updateAt,
    a.create_user_id as createUserId,
    a.update_user_id as updateUserId,
    b.name as userName
    from t_operation_log a
    inner join (
        select
            user_id,name
        from
            t_user
        <where>
            <if test="userName!=null and userName!=''">
                name like concat('%',#{userName},'%')
            </if>
        </where>
        ) b on a.user_id = b.user_id
    where 1=1
    <if test="operation_module!=null and operation_module!=''">
        and a.operation_module like concat('%',#{operation_module},'%')
    </if>
    <if test="operation_detail!=null and operation_detail!=''">
        and a.operation_detail like concat('%',#{operation_detail},'%')
    </if>
    <if test="operation_createAt!=null and operation_updateAt!=null and operation_createAt!='' and operation_updateAt !=''">
       and date_format(a.operation_time,'%Y-%m-%d') between date_format(#{operation_createAt},'%Y-%m-%d') and date_format(#{operation_updateAt},'%Y-%m-%d')
    </if>
</select>

5.大于小于范围查询

<if test="ticket_left != null  and  ticket_right != null">
    and  ticket  &gt; #{ticket_left} and ticket &lt;= #{ticket_right}
</if>

6.两表关联查询封装到实体里面的实体

    <resultMap id="collectionCarMap" type="com.jf3q.demo.bean.OrderInfo">
        <id property="id" column="id"></id>
        <result property="buyUserId" column="user_id"></result>
        <result property="carId" column="car_id"></result>
        <result property="createTime" column="create_time"></result>
        <result property="payTime" column="pay_time"></result>
        <result property="orderCode" column="order_code"></result>
        <result property="orderPrice" column="order_price"></result>
        <result property="seeState" column="see_state"></result>
        <result property="payState" column="pay_state"></result>
        <result property="isok" column="isok"></result>
        <association property="carinfo" column="car_id" javaType="com.jf3q.demo.bean.Carinfo">
            <id property="id" column="id"></id>
            <result property="userId" column="user_id"></result>
            <result property="brand" column="brand"></result>
            <result property="title" column="title"></result>
            <result property="carPrice" column="car_price"></result>
            <result property="carYear" column="car_year"></result>
            <result property="mileage" column="mileage"></result>
            <result property="gearbox" column="gearbox"></result>
            <result property="carImg" column="car_img"></result>
            <result property="carContent" column="car_content"></result>
            <result property="certification" column="certification"></result>
            <result property="carCity" column="car_city"></result>
        </association>
    </resultMap>
    <select id="getList" resultMap="collectionCarMap" parameterType="com.jf3q.demo.bean.OrderInfo">
        SELECT
        a.*, b.*,c.phone as buyUserPhone,c.nickname as buyUserNickname
        FROM
        orderinfo a
        LEFT JOIN  carinfo b  on a.car_id=b.id
        LEFT JOIN  userinfo c  on a.buy_user_id=c.id
        WHERE 1=1
        <if test="buyUserPhone!= null and buyUserPhone != ''">
            and  c.phone like concat('%',#{buyUserPhone},'%')
        </if>
        <if test="buyUserNickname!= null and buyUserNickname != ''">
            and  c.nickname like concat('%',#{buyUserNickname},'%')
        </if>
        <if test="buyUserId!= null ">
            and a.buy_user_id= #{buyUserId}
        </if>
        <if test="saleUserId!= null ">
            and a.sale_user_id= #{saleUserId}
        </if>
        <if test="carId!= null ">
            and a.car_id= #{carId}
        </if>
        <if test="seeState!= null ">
            and a.see_state= #{seeState}
        </if>
        <if test="payState!= null ">
            and a.pay_state= #{payState}
        </if>
        <if test="isok!= null ">
            and a.isok= #{isok}
        </if>
    </select>

订单实体类

 @TableId(type = IdType.AUTO)
    private Integer id;
    private String orderCode;//订单编号
    private Integer carId;//汽车ID
    private Integer buyUserId;//买车用户ID
    private Integer saleUserId;//卖车用户ID
    private Double orderPrice;//订单金额
    private String createTime;//下单时间
    private String payTime;//支付时间
    private Integer seeState;//看车状态：0待看车 1已看车
    private Integer payState;//支付状态0待支付，1已支付
    private Integer isok;//出售状态（-1 待成交 0未成交，1已成交）
    @TableField(exist = false)
    private String buyUserPhone;//用户手机号
    @TableField(exist = false)
    private String buyUserNickname;//用户昵称
    @TableField(exist = false)
    private Carinfo carinfo;//购买的车

汽车实体类

public class Carinfo {
    @TableId(type = IdType.AUTO)
    private Integer id;
    private Integer userId;//用户ID
    private String title;
    private String brand;
    private Double carPrice;//价格;(总得售价)
    private Double depositPrice;//定金
    private String carYear;//出厂年份;
    private String mileage;//里程;
    private Integer gearbox;//变速箱（0手自一体 1手动档 2自动挡）
    private String carImg;//车的封面;
    private String carContent;//车的详细信息;
    private String carArchives;//车的档案信息（维修保养记录）
    private String createTime;//发布时间;
    private Integer state;//状态;(0下架 1上架)
    private Integer certification;//是否认证，1是0否
    private String carCity;//所在城市（精确到区）
    private String address;//看车地址
    private String imgs;//车的照片（多张）
    @TableField(exist = false)
    private  String userNickName;
    @TableField(exist = false)
    private  String userPhone;
    @TableField(exist = false)
    private  Boolean isCollection;//登陆者是否收藏
}

参考文章联表查询
https://www.cnblogs.com/yuqingya/p/12012604.html

插入的时候返回主键key

   @Insert("INSERT INTO ...")
    @Options(useGeneratedKeys = true, keyProperty = "id", keyColumn = "id")
    void insertOrder(Order order);