我正在尝试从以下脚本中选择每个客户站点的最新行：
select "CUSTOM_ATTRIBUTE"."VALUE" as "SO_NUMBER",
"CONTRACT"."END_DATE" as "CONTRACT_END_DATE",
"ALERT"."LAST_UPDATED_TIMESTAMP" as "LAST_UPDATED_TIMESTAMP_1",
"DATA_POINT_UPLOAD_DATA"."VALUE" as "DP_UPLD_DATA_VALUE",
"SITE"."NAME" as "SITE_NAME",
"SITE"."LAST_UPDATED_TIMESTAMP" as "LAST_UPDATED_TIMESTAMP",
"CONTRACT_TYPE"."NAME" as "CONTRACT_TYPE_NAME",
"ALERT"."USER_ID" as "ALERT_USER_ID",
"ALERT"."ACKNOWLEDGEMENT_TIME" as "NOTES_TIMESTAMP",
"ALERT"."EVENT" as "ALERT_EVENT",
"ALERT"."ACKNOWLEDGEMENT_NOTE" as "NOTES",
"ALERT"."CASE_NO" as "ALERT_CASE_NO",
"SITE"."ID" as "SITE_ID"
from "DB"."ALERT" "ALERT",
"DB"."DATA_POINT_UPLOAD_DATA" "DATA_POINT_UPLOAD_DATA",
"DB"."COMPONENT" "COMPONENT",
"DB"."COMPONENT_DATA_POINT" "COMPONENT_DATA_POINT",
"DB"."CONTRACT" "CONTRACT",
"DB"."CONTRACT_TYPE" "CONTRACT_TYPE",
"DB"."CUSTOM_ATTRIBUTE" "CUSTOM_ATTRIBUTE",
"DB"."SITE" "SITE"
where "SITE"."ID"="CUSTOM_ATTRIBUTE"."SITE_ID"
and "CUSTOM_ATTRIBUTE"."SITE_ID"="CONTRACT"."SITE_ID"
and "CONTRACT"."CONTRACT_TYPE_ID"="CONTRACT_TYPE"."ID"
and "CUSTOM_ATTRIBUTE"."SITE_ID"="COMPONENT"."SITE_ID"
and "COMPONENT"."ID"="COMPONENT_DATA_POINT"."COMPONENT_ID"
and "COMPONENT_DATA_POINT"."ID"="DATA_POINT_UPLOAD_DATA"."COMPONENT_DATA_POINT_ID"
and "ALERT"."SITE_ID"="CUSTOM_ATTRIBUTE"."SITE_ID"
and "CUSTOM_ATTRIBUTE"."NAME" ='SO#'
and "COMPONENT_DATA_POINT"."NAME" ='State'
and "SITE"."EQUIPMENT_TYPE_ID" ='250';
当前输出：
...... 5,000输出......
SO_NUMBER CONTRACT_END_DATE LAST_UPDATED_TIMESTAMP_1 DP_UPLD_DATA_VALUE SITE_NAME LAST_UPDATED_TIMESTAMP CONTRACT_TYPE_NAME ALERT_USER_ID NOTES_TIMESTAMP ALERT_EVENT NOTES ALERT_CASE_NO SITE_ID
------------------------------ ----------------- ----------------------------------- ---------------------------------------------------------------------------------------------------- ---------------------------------------------------------------------------------------------------- ----------------------------------- -------------------------------------------------- --------------------------------------- ----------------------------------- -------------------------------------------------- ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ -------------------------------------------------- ----------
144732 30-JUN-19 14-JUN-17 04.57.07.119266000 AM Some_Event_Occurred Customer Name 10-NOV-16 08.19.47.000000000 PM Some Contract 1169 09-JUN-17 03.34.10.019229000 PM Some Notes Entered ABC123
Only 5,000 rows currently supported in a script results
5,000 rows selected
预期产出：
SO_NUMBER CONTRACT_END_DATE LAST_UPDATED_TIMESTAMP_1 DP_UPLD_DATA_VALUE SITE_NAME LAST_UPDATED_TIMESTAMP CONTRACT_TYPE_NAME ALERT_USER_ID NOTES_TIMESTAMP ALERT_EVENT NOTES ALERT_CASE_NO SITE_ID
------------------------------ ----------------- ----------------------------------- ---------------------------------------------------------------------------------------------------- ---------------------------------------------------------------------------------------------------- ----------------------------------- -------------------------------------------------- --------------------------------------- ----------------------------------- -------------------------------------------------- ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ -------------------------------------------------- ----------
145732 30-JUN-19 14-JUN-17 04.57.07.119266000 AM Some_Run_Event Customer 1 10-NOV-16 08.19.47.000000000 PM Contract 1169 09-JUN-17 03.34.10.019229000 PM 100763
146733 30-JUN-19 10-JUN-17 03.20.06.396989000 AM Some_Run_Event Customer 2 10-NOV-16 08.19.47.000000000 PM Contract 100764
144734 30-JUN-19 10-JUN-17 03.29.07.172041000 AM Some_Run_Event Customer 3 10-NOV-16 08.19.47.000000000 PM Contract 100765
144835 30-JUN-19 10-JUN-17 03.44.06.692450000 AM Some_Run_Event Customer 4 10-NOV-16 08.19.47.000000000 PM Contract 100766
144936 30-JUN-19 10-JUN-17 06.30.06.828320000 AM Some_Run_Event Customer 5 10-NOV-16 08.19.47.000000000 PM Contract 100767
144937 30-JUN-19 10-JUN-17 06.58.06.163756000 AM Some_Run_Event Customer 6 10-NOV-16 08.19.47.000000000 PM Contract 100768
我正在尝试从每个站点ID获取最新行，而不是从每个站点ID获取数千行。
答案 0 :(得分：1)
假设＆＃34;最新＆＃34;你的意思是alert.last_updated_timestamp中的最新日期，然后创建一个子查询，该子查询使用聚合来获取每个SiteID的此日期的max（）值，然后将该子查询连接到您已经拥有的查询，将输出限制为那些时间
或者如果＆＃34;最新＆＃34;意味着别的东西，然后相应地调整;相同的技术将适用。
答案 1 :(得分：0)
使用
“SITE”。“ID”为“SITE_ID”，
ROW_NUMBER（）over（由ALITE.LAST_UPDATED_TIMESTAMP desc按SITE.ID顺序划分）为temp_col
作为现有select语句的最后一列，并添加一个外部查询来过滤SELECT * FROM（....现有查询），其中temp_col = 1