Home | About | Sematext search-lucene.com search-hadoop.com
 Search Hadoop and all its subprojects:

Switch to Plain View
HBase >> mail # user >> Using doubles and longs as ordering row values

Jonathan Bishop 2012-11-05, 18:41
Jean-Daniel Cryans 2012-11-05, 19:38
anil gupta 2012-11-05, 22:57
Copy link to this message
Re: Using doubles and longs as ordering row values
Have a look at the lily library. It has code to encode Longs/Doubles into bytes such that resulting bytes sort as expected based on the numbers.

-- Lars

 From: Jonathan Bishop <[EMAIL PROTECTED]>
Sent: Monday, November 5, 2012 10:41 AM
Subject: Using doubles and longs as ordering row values

In my application my row values are doubles. I would like my scans to
traverse the rows in order of increasing values.

But if I simply use

double d  = ....
byte[] row = Bytes.toBytes(d);

I will get an ordering which is based on the byte values of doubles, not on
the value of the doubles themselves.

I see also that integer values have the same issue due to the first bit
being the sign bit. So negative values will come after positive values.

Any suggestions?


Dave Latham 2012-11-06, 00:26
Dave Latham 2012-11-06, 00:27
Jonathan Bishop 2012-11-06, 05:07
David Koch 2012-12-01, 15:01
Marcos Ortiz 2012-12-01, 15:27