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HBase >> mail # user >> Column qualifiers with hierarchy and filters

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Re: Column qualifiers with hierarchy and filters
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.

2: abc

would appear in the above sequence, which is out of order when doing prefix
filtering. Zero padding could fix this:

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

> 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