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HBase >> mail # user >> Using doubles and longs as ordering row values


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Jonathan Bishop 2012-11-05, 18:41
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Jean-Daniel Cryans 2012-11-05, 19:38
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anil gupta 2012-11-05, 22:57
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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]>
To: "[EMAIL PROTECTED]" <[EMAIL PROTECTED]>
Sent: Monday, November 5, 2012 10:41 AM
Subject: Using doubles and longs as ordering row values
 
Hi,

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?

Thanks,

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