AQI计算

lizijie

2019-08-08 a6ff89dd8eed9ea4e6162ff5491d4583e4ef621a

 src/main/resources/mapper/QualityDailyMapper.xml

@@ -1,6 +1,7 @@
<?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.moral.mapper.QualityDailyMapper">

<!-- 
   <select id="getQualityCountDayByRegion" resultType="map">

      SELECT

         COUNT( * ) count 

@@ -13,4 +14,32 @@
         AND quality &lt; 3      

      </where>

   </select>

 -->



   <select id="getQualityCountDayByRegion" resultType="map">

      SELECT COUNT(*) count

      FROM (

         SELECT

            MAX(CASE aqi_json ->> '$.quality' 
                  WHEN "优" THEN 1 
                  WHEN "良" THEN 2 
                  WHEN "轻度污染" THEN 3 
                  WHEN "中度污染" THEN 4 
                  WHEN "重度污染" THEN 5 
                  WHEN "严重污染" THEN 6 
                  ELSE 0 END

            )   AS quality

         FROM

            `hangzhou_aqi` 
         <where>

            time >= #{start} 
            AND time &lt; #{end} 
            AND city_code = #{cityCode} 
         </where>

         GROUP BY DATE_FORMAT( time, '%Y-%m-%d' )

      ) t

      <where>

         t.quality &lt; 3

      </where>

   </select>

</mapper>