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From DuyHai Doan <doanduy...@gmail.com>
Subject Re: Bitmaps
Date Mon, 06 Oct 2014 20:56:10 GMT
Isn't there a video of Ooyala at some past Cassandra Summit demonstrating
usage of Cassandra for text search using Trigram ? AFAIK they were storing
kind of bitmap to perform OR & AND operations on trigram

On Mon, Oct 6, 2014 at 10:53 PM, Russell Bradberry <rbradberry@gmail.com>
wrote:

> I highly recommend against storing data structures like this in C*. That
> really isn't it's sweet spot.  For instance, if you were to use the blob
> type which will give you the smallest size, you are still looking at a cell
> size of (90,000,000/8/1024) = 10,986 or over 10MB in size, which is
> prohibitively large.
>
> Additionally, there is no way to modify the bitmap in place, you would
> have to read the entire structure out and write it back in.
>
> You could store one bit per cell, but that would essentially defeat the
> purpose of the bitmap's compact size.
>
> On Mon, Oct 6, 2014 at 4:46 PM, Eduardo Cusa <
> eduardo.cusa@usmediaconsulting.com> wrote:
>
>> Hi Guys, what data type recommend to store bitmaps?
>> I am planning to store maps of 90,000,000 length and then query by key.
>>
>> Example:
>>
>> key : 22_ES
>> bitmap : 101011111101010111010101011........
>>
>>
>>
>> Thanks
>> Eduardo
>>
>>
>>
>

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