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Avro, mail # user - Grouping comparators - old vs new mapreduce APIs


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Dave Beech 2012-12-11, 15:11
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Re: Grouping comparators - old vs new mapreduce APIs
Doug Cutting 2012-12-11, 17:55
On Tue, Dec 11, 2012 at 7:11 AM, Dave Beech <[EMAIL PROTECTED]> wrote:
> What this means is, if you want to use a grouping comparator with the "new"
> mapreduce API and Avro, you absolutely must provide an implementation of
> RawComparator, or do the deserialization and delegating method call to
> compare(x,y) yourself. This really isn't obvious and I haven't found it to
> be documented anywhere.

Sounds like we should at least add some documentation and probably
also make this simpler.  Perhaps we could provide a subclass of
AvroKeyComparator that does the deserialization and delegates to
compare(x,y)?  Then folks can subclass this and override compare(x,y)?

Doug
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Dave Beech 2012-12-12, 08:53