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From Andrey Stepachev <oct...@gmail.com>
Subject Re: Scanning half a key or value in HBase
Date Wed, 18 Aug 2010 05:31:50 GMT
2010/8/17 Ryan Rawson <ryanobjc@gmail.com>:
> Hey,
> If you are scanning fixed-width keys, eg: binary conversions of longs,
> then the [start,start+1) solution works.

Why? It will work for any byte array, if we want to prefix scan. And no matter,
what key encoding we use.

If we look at first email question, we see '<first_half_of_key>%', so
if first_half_of_key = 'foo'
we _should_ get all keys foo, foo:, foo1234, because we want this.

My solution was to convert requested first_half_of_key to byte[] arr = ...
Then do  (pseudocode)
arr = toBytes(first_half_of_key)
arr2 = arr.clone(),
STOPROW = arr2;

This gives us real stop key, which will be greater, then any key,
prefixed with given prefix
(due of nature of binary comparators, used by hbase).

Or I missed something ?

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