Partition Key in Cassandra -

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if in cassandra cf, rowkey (a, b, c) , data highly skewed cardinality of being let's one. entire data reside on single node of cassandra cluster if replication factor 1?

also, if node down, exception get?

if have 1 partition key , rf 1 not able access data if node row hashes down. unavailable exception.

http://www.datastax.com/drivers/java/2.1/com/datastax/driver/core/exceptions/unavailableexception.html

primary key ((a),b,c) or primary key (a,b,c) means a decides node data resides on.

primary key ((a,b),c) mean using composite key , combination of a , b deterimines node is.

primary key ((a,b,c)) means full combination of a, b, , c used decide correct node.

all of variables not in first set of inner parenthesis act clustering keys , determine sorted order of data within row not node row placed on.


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