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From Javier Canillas <>
Subject Re: Understanding Indexes
Date Thu, 24 Feb 2011 12:12:11 GMT
I dont think i got the point in your question. But if you are thinking
about key indexes (like PKs), take in mind that cassandra will manage
keys using the partition strategy. By doing so, it will be able to
determine on which node the row with such key should be hold.
So, in another words, inside cassandra, each column family is treated
as a big table (hashtable). Taking this last in mind, there is no need
to have an index by key. Would you put an index over a hashtable's

Enviado desde mi iPhone

El 23/02/2011, a las 19:50, mcasandra <> escribió:

> So far my understanding about indexes is that you can create indexes only on
> column values (username in below eg).
> Does it make sense to also have index on the keys that columnFamily uses to
> store rows (row keys "abc" in below example). I am thinking in an event rows
> keep growing would search be fast if there is an index on row keys if you
> want to retrieve for eg "def" only out of tons of rows?
> UserProfile = { // this is a ColumnFamily
>    abc: {   // this is the key to this Row inside the CF
>        // now we have an infinite # of columns in this row
>        username: "phatduckk",
>        email: "",
>        phone: "(900) 976-6666"
>    }, // end row
>    def: {   // this is the key to another row in the CF
>        // now we have another infinite # of columns in this row
>        username: "ieure",
>        email: "",
>        phone: "(888) 555-1212"
>        age: "66",
>        gender: "undecided"
>    },
> }
> 2) Is the hash of column key used or row key used by RandomPartitioner to
> distribute it accross the cassandra nodes?
> --
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