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HBase, mail # user - Column qualifiers with hierarchy and filters


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Re: Column qualifiers with hierarchy and filters
Jean-Marc Spaggiari 2013-11-05, 17:28
Hi Nasron,

Why are you saying that it's a limited way? Does it achieve your needs?
2013/11/4 Nasron Cheong <[EMAIL PROTECTED]>

> An example query would be the following, say the column qualifier was of
> the form
>
> <bucket #>:<msg type>
>
> where <bucket #> should be an integer value, and msg type is a string. E.g.
>
> 1:abc
> 1000:abc
> 2: abc
>
> would appear in the above sequence, which is out of order when doing prefix
> filtering. Zero padding could fix this:
>
> 0001:abc
> 0002:abc
> 1000: abc
>
> But is a limited way of ensuring the sequence of CQ (column qualifiers) is
> correct, in order for prefix filtering to work. Are there other options?
>
> - Nasron
>
>
> On Thu, Oct 31, 2013 at 9:19 PM, Nasron Cheong
> <[EMAIL PROTECTED]>wrote:
>
> > Hi,
> >
> > I'm trying to determine the best way to serialize a sequence of
> > integers/strings that represent a hierarchy for a column qualifier, which
> > would be compatible with the ColumnPrefixFilters, and BinaryComparators.
> >
> > However, due to the lexicographical sorting, it's awkward to serialize
> the
> > sequence of values needed to get it to work.
> >
> > What are the typical solutions to this? Do people just zero pad integers
> > to make sure they sort correctly? Or do I have to implement my own
> > QualifierFilter - which seems expensive since I'd be deserializing every
> > byte array just to compare.
> >
> > Thanks
> >
> > - Nasron
> >
>