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From Alex Vasilenko <aa.vasile...@gmail.com>
Subject Re: row filter - binary comparator at certain range
Date Thu, 09 Feb 2012 19:57:04 GMT
Ted,

Scan#setTimeRange filters columns, not rows, I think it's not optimal,
because all rows, including columns will be read. In case of
BinaryRangeComparator rows not in range will be filtered out earlier.

Thanks,
Alexandr Vasilenko

2012/2/9 Ted Yu <yuzhihong@gmail.com>

> Alex:
> Does the timestamp below reflect actual time ?
> If so, take a look at the following method (and its javadoc) in Scan.java:
>  public Scan setTimeRange(long minStamp, long maxStamp)
>
> Cheers
>
> On Thu, Feb 9, 2012 at 11:08 AM, Alex Vasilenko <aa.vasilenko@gmail.com
> >wrote:
>
> > Lars,
> >
> > But how it will behave, when I have salt at the beginning of the key to
> > properly shard table across regions? Imagine row key of format
> > salt:timestamp and rows goes like this:
> > ...
> > 1:15
> > 1:16
> > 1:17
> > 1:23
> > 2:3
> > 2:5
> > 2:12
> > 2:15
> > 2:19
> > 2:25
> > ...
> >
> > And I want to find all rows, that has second part (timestamp) in range
> > 15-25. What startKey and endKey should be used?
> >
> > Alexandr Vasilenko
> > Web Developer
> > Skype:menterr
> > mob: +38097-611-45-99
> >
> >
> > 2012/2/9 lars hofhansl <lhofhansl@yahoo.com>
> >
> > > Sorry misunderstood your question.
> > >
> > > In that case you'd just use a scanner (see Scan.java) and set that
> > > startKey and the endKey.
> > > That will give you that range of keys and it do so efficiently, as it
> can
> > > seek forward to the startKey.
> > >
> > > -- Lars
> > >
> > >
> > >
> > > ________________________________
> > >  From: Alex Vasilenko <aa.vasilenko@gmail.com>
> > > To: user@hbase.apache.org
> > > Sent: Thursday, February 9, 2012 10:40 AM
> > > Subject: Re: row filter - binary comparator at certain range
> > >
> > > Lars,
> > >
> > > I meant range of row keys. BinaryPrefixComparator can be used in
> > > conjunction with RowFilter to filter by prefix.
> > >
> > > Alex
> > >
> > > 2012/2/9 lars hofhansl <lhofhansl@yahoo.com>
> > >
> > > > Note the BinaryPrefixComparator compares values (not keys).
> > > > Not sure that this is what you want, but you mention a "range of
> key".
> > > >
> > > >
> > > > For keys there are ColumnPrefixFilter and ColumnRangeFilter.
> > > >
> > > >
> > > > -- Lars
> > > >
> > > >
> > > >
> > > > ________________________________
> > > >  From: Alex Vasilenko <aa.vasilenko@gmail.com>
> > > > To: user@hbase.apache.org
> > > > Sent: Thursday, February 9, 2012 10:03 AM
> > > > Subject: row filter - binary comparator at certain range
> > > >
> > > > Hi all,
> > > >
> > > > I'm a brand new user of hbase and hadoop in general. Trying to
> evaluate
> > > > hbase for our needs. Question is: why there's BinaryPrefixComparator,
> > but
> > > > no BinaryRangeComparator, where you specify what range of key should
> be
> > > > compared. Are there any concerns about using it?
> > > >
> > > > Thanks,
> > > > Alexandr Vasilenko
> > > >
> > >
> >
>

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