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From Alex Vasilenko <aa.vasile...@gmail.com>
Subject Re: row filter - binary comparator at certain range
Date Fri, 10 Feb 2012 09:22:45 GMT
Let me rephrase my question a bit: what common pattern of row key for
time-series data?  OpenTSDB schema is a common reference, but it's limited
to per-metric time-series data.

Regards,
Alex

2012/2/9 Alex Vasilenko <aa.vasilenko@gmail.com>

> 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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