mapper.xml里面的sql语句

稍微复杂点的 ，参数类型为

parameterType="java.util.HashMap"

返回类型为resultMap 

SELECT
   t.brand_id AS id,
    ifnull(SUM(t.day_wholesale),0) AS day_wholesale,
    ifnull(sum(t.day_retail),0) AS day_retail,
    ifnull(sum(t.month_w_task),0) AS w_task,
    ifnull(sum(t.w_total_task),0) AS w_total_task,
    ifnull(sum(t.month_r_task),0) AS r_task,
    ifnull(sum(t.r_total_task),0) AS r_total_task,
    ifnull(sum(t.society_inhouse_sum),0) AS society_inhouse_sum,
    ifnull(sum(t.society_in_transit),0) AS society_in_transit,
    ifnull(sum(t.society_no_send),0) AS society_no_send,
    ifnull(sum(t.day30_retail),0) AS day30_retail,
   ifnull(
      sum(t.society_inhouse_sum),
      0
   ) + ifnull(sum(t.society_no_send), 0) + ifnull(
      sum(t.society_in_transit),
      0
   ) AS stock_sum,
    ifnull(SUM(t.date1),0) AS date1,
    ifnull(SUM(t.date2),0) AS date2,
    ifnull(SUM(t.date3),0) AS date3,
    ifnull(SUM(t.date4),0) AS date4,
    ifnull(SUM(t.date5),0) AS date5
FROM
   ca_dealer_express t
where
    t.date = #{date}
    and dealer_id = #{dealer_id}
    and t.c_type=0
    <if test="brand_id!=null">
      and t.brand_id =#{brand_id}
      group by brand_id
    </if>

 

其中sql查询条件通常把能筛选出的东西少的条件放前面，通常是把整型放前面，而本例特殊，因此是把字符串放前面，一面产生是list时，也要放到后面，这样会提速