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From samal <samalgo...@gmail.com>
Subject Re: Query on how to count the total number of rowkeys and columns in them
Date Thu, 24 May 2012 06:55:04 GMT
default count is 100, set this to some max value, but this won't guarantee
actual count.

Something like paging can help in counting. Get the last key as start in
second query, end as null, count as some value. But this will port data to
client where as we only need count.

Other solution may be (if count is very necessary) having separate counter
CF, incr whenever key is inserted in other CF.

I will not use Thrift API, clients library is very mature [1] & CQL is also
very good.

[1]
http://pycassa.github.com/pycassa/api/pycassa/columnfamily.html#pycassa.columnfamily.ColumnFamily.get_range

/Samal

On Thu, May 24, 2012 at 11:52 AM, Prakrati Agrawal <
Prakrati.Agrawal@mu-sigma.com> wrote:

>  Hi****
>
> ** **
>
> I am trying to learn Cassandra and I have one doubt. I am using the Thrift
> API, to count the number of row keys I am using KeyRange to specify the row
> keys. To count all of them, I specify the start and end as “new byte[0]”.
> But the count is set to 100 by default. How do I use this method to count
> the keys if I don’t know the actual number of keys in my Cassandra
> database? Please help me****
>
> ** **
>
> Prakrati Agrawal | Developer - Big Data(I&D)| 9731648376 |
> www.mu-sigma.com ****
>
> ** **
>
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