hive踩坑记录

一个表以年月日分区，以如下函数的计算结果查询，分区不起作用，会全表扫描

SELECT year( from_unixtime(unix_timestamp() - 3600*24*7,'yyyy-MM-dd')  ) as year,
 month( from_unixtime(unix_timestamp() - 3600*24*7,'yyyy-MM-dd') ) as mon,
  day( from_unixtime(unix_timestamp() - 3600*24*7,'yyyy-MM-dd') ) as day

以如下的结果查询似乎是可行的，出结果非常快

SELECT * from xxxx
where  (year=year(date_sub(CURRENT_DATE,1))
and mon=month(date_sub(CURRENT_DATE,1))
and day = day(date_sub(CURRENT_DATE,1))

 

来源：oschina

链接：https://my.oschina.net/fdayok/blog/4695327