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From lars hofhansl <la...@apache.org>
Subject Re: Hbase multiget vs scan with RowFilter
Date Thu, 05 Feb 2015 06:07:35 GMT
It depends.
A scan will always scan all rows between the passed start and stop rows (or all rows when
none where passed). A Filter can filter rows out, but they will all be read in.A MultiGet
does a seek (in a sense) for each Get.
So if the set of Gets in the MultiGet is very small compared to the total number of rows you
need to scan you'll be better off with that.If you can limit the set of rows to scan (i.e.
there is a start and stop row not too far apart) a scan is faster.
The numbers depend on many variables but Scan'ning a row in a larger set is probably 100-1000x
faster than Get'ing a single row.
-- Lars

      From: alokob <alokob.be@gmail.com>
 To: user@hbase.apache.org 
 Sent: Wednesday, February 4, 2015 8:53 PM
 Subject: Re: Hbase multiget vs scan with RowFilter
   
Thanks Ted for your reply.

I was under impression that scan with RowFilter would give better
performance as in case of multi-get each Get would be treated as an
independent scan. Or you mean to say that in case scan it would be full
table scan but in case of multi-get it would be return once we get the row
without continuing to scan , so multi-get would be efficient.



--
View this message in context: http://apache-hbase.679495.n3.nabble.com/Hbase-multiget-vs-scan-with-RowFilter-tp4068066p4068108.html


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