bq. I believe you can batch into one call.
See the following API in HTable for batching Get's :
public Result[] get(List<Get> gets) throws IOException {
On Tue, Apr 29, 2014 at 4:43 PM, Rendon, Carlos (KBB) <[email protected]>wrote:
> 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:[email protected]]
> Sent: Tuesday, April 29, 2014 4:36 PM
> To: [email protected]
> 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?
>
