這裏需要使用到oracle的over()函數
over()函數寫法over(partition by expr2 order by expr3),根據expr2對結果進行分區,在各分區內按照expr3進行排序;
over函數不能單獨使用,需要與row_number(),rank()和dense_rank,lag()和lead(),sum()等配合使用。
select CREATEDATE,COMNAME,PV from (
select CREATEDATE,COMNAME,PV
from (select distinct TO_CHAR(T.CREATEDATE,'YYYY-MM-DD') CREATEDATE,T.COMNAME,T.PV, RANK() OVER(PARTITION BY T.CREATEDATE ORDER BY T.ROWID) RK
from T_BIG_MERGE_THREE_TABLE T where T.IS_TMSF = 0 and T.IS_LP = 0)
where RK <![CDATA[<=]]> 10 order by CREATEDATE desc)
where rownum <![CDATA[<=]]> 70
這裏爲什麼要ORDER BY T.ROWID有點困惑,order by其他的只能取前70條記錄,不能每天取10條