Oracle SQL练习之Sum,Count,Decode,Case…When的使用

最近在做报表，写了一些SQL,整理一下，其中涉及到Oracle很多语法的使用，方便大家参考与复习！

SELECT      RESULT.SITE_ID,RESULT.SITE_NAME,RESULT.STATION_TYPE,RESULT.STATION_NAME,RESULT.MONITOR_TIME,RESULT.PROJECT_ID,RESULT.PROJECT_NAME,RESULT.MONITOR_RESULT,RESULT.IF_GUARD_LEVEL,         --根据水情站点类型和监测指标统计站点数目         COUNT(1) over (partition by RESULT.STATION_TYPE || RESULT.PROJECT_ID) TOTAL_COUNT,         --根据水情站点类型和监测指标统计正常站点数目         --SUM(CASE WHEN RESULT.IF_GUARD_LEVEL = 'YES' THEN 1 ELSE 0 END) over (partition by RESULT.STATION_TYPE || RESULT.PROJECT_ID) NORMAL_COUNT,         SUM(DECODE(RESULT.IF_GUARD_LEVEL,'YES',1,0)） over (partition by RESULT.STATION_TYPE || RESULT.PROJECT_ID) NORMAL_COUNT,         --根据水情站点类型和监测指标统计异常站点数目         --SUM(CASE WHEN RESULT.IF_GUARD_LEVEL = 'YES' THEN 0 ELSE 1 END) over (partition by RESULT.STATION_TYPE || RESULT.PROJECT_ID) UNNORMAL_COUNT         SUM(DECODE(RESULT.IF_GUARD_LEVEL,'YES',0,1)） over (partition by RESULT.STATION_TYPE || RESULT.PROJECT_ID) UNNORMAL_COUNT     FROM     (     --查询每个站点最新一条实时监控数据         SELECT * FROM          (                 SELECT                       R.SITE_ID,                      B."NAME" AS SITE_NAME,                      B.STATION_TYPE,                      DICT."NAME" AS STATION_NAME,                      TO_CHAR(R.MONITOR_TIME,'yyyy-MM-dd HH:mm') AS MONITOR_TIME,                      R.PROJECT_ID,                      D."NAME" AS PROJECT_NAME,                      R.MONITOR_RESULT,                      R.IF_GUARD_LEVEL,                      --查询同一个站点同一个指标的最新一条记录                      ROW_NUMBER() OVER(PARTITION BY R.SITE_ID,R.PROJECT_ID ORDER BY R.MONITOR_TIME DESC) RN                 FROM T_WATER_REALTIME_RESULT R                 LEFT JOIN V_WATER_SITE_BASE_INFO B ON B."ID" = R.SITE_ID                 LEFT JOIN PLATFORM_DICTIONARY_DATA DICT ON DICT."VALUE" = B.STATION_TYPE AND DICT.CODE = 'WATER_TYPE'                 LEFT JOIN PLATFORM_DICTIONARY_DATA D ON R.PROJECT_ID = D."VALUE" AND D.CODE = 'WATER_PROJECT_TYPE'                 WHERE 1=1                  AND B.IF_NEW = 'YES'                 ORDER BY R.MONITOR_TIME DESC,R.SITE_ID             ) T          WHERE T.RN = 1     ) RESULT  ORDER BY RESULT.STATION_TYPE,RESULT.MONITOR_TIME DESC