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From "Rendon, Carlos (KBB)" <CRen...@kbb.com>
Subject RE: Help with row and column design
Date Tue, 29 Apr 2014 23:43:29 GMT
You don't do a scan, you do a series of gets, which I believe you can batch into one call.

last 5 days query in pseudocode
res1 = Get( hash("2014-04-29") + "2014-04-29")
res2 = Get( hash("2014-04-28") + "2014-04-28")
res3 = Get( hash("2014-04-27") + "2014-04-27")
res4 = Get( hash("2014-04-26") + "2014-04-26")
res5 = Get( hash("2014-04-25") + "2014-04-25")

For each result you look for the particular column or columns you are interested in
Total_usa = res1.get("c:usa") + res2.get("c:usa") + res3.get("c:usa") + ... 
Total_female_usa = res1.get("c:usa:sex:f") + ...

"What happens when we add more fields? Do we just keep adding in more column qualifiers? If
so, how would we filter across columns to get an aggregate total?"

Yes. See total_usa vs. total_female_usa above. Basically you have to pre-store every level
of aggregation you care about.

-----Original Message-----
From: Software Dev [mailto:static.void.dev@gmail.com] 
Sent: Tuesday, April 29, 2014 4:36 PM
To: user@hbase.apache.org
Subject: Re: Help with row and column design

> The downside is it still has a hotspot when inserting, but when 
> reading a range of time it does not

How can you do a scan query between dates when you hash the date?

> Column qualifiers are just the collection of items you are aggregating 
> on. Values are increments. In your case qualifiers might look like 
> c:usa, c:usa:sex:m, c:usa:sex:f, c:italy:sex:m, c:italy:sex:f, 
> c:italy,

What happens when we add more fields? Do we just keep adding in more column qualifiers? If
so, how would we filter across columns to get an aggregate total?
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