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Posted to user@cassandra.apache.org by Mark Jones <MJ...@imagehawk.com> on 2010/04/30 05:37:16 UTC
How does cassandra deal with collisions?
MD5 is not a perfect hash, it can produce collisions, how are these dealt with?
Is there a size appended to them?
If 2 keys collide, would that result in a merging of data (if the column names aren't the same) or an overwrite if they were?
Re: How does cassandra deal with collisions?
Posted by Sylvain Lebresne <sy...@yakaz.com>.
Two rows are never compared by the MD5 of their keys. The md5 of a row key is
just used to choose which nodes of the cluster are responsible for the row.
On Fri, Apr 30, 2010 at 5:37 AM, Mark Jones <MJ...@imagehawk.com> wrote:
> MD5 is not a perfect hash, it can produce collisions, how are these dealt
> with?
>
> Is there a size appended to them?
>
>
>
> If 2 keys collide, would that result in a merging of data (if the column
> names aren’t the same) or an overwrite if they were?