-Some questions on hive SELECT/UNION - how to do multiple counts in one query?
Vijay 2009-08-13, 23:42
I have some questions about using SELECT with UNION. I have a number of
access log files that I want to process to select counts per day matching a
specific pattern in the URL. This is very simple with a select:
SELECT day, count(1) FROM accesslogs WHERE request like '%foo%' group by day
order by day;
However, when I need to count multiple patterns (count of requests like
'%foo%', like '%bar%', etc), I'm not able to find the right query. I made
some attempts with UNION ALL and such but none of them really worked.
Ultimately I'm trying to get some numbers like this:
<day>, <count matching %foo%>, <count matching %bar%>
Is there a way of doing this with a single query? I know I can do it with
multiple queries and such but that seems like such a waste of time and
I hope my question is clear.