Column (data store)

A column of a distributed data store is a NoSQL object of the lowest level in a keyspace.

It is a tuple (a key–value pair) consisting of three elements: A column is used as a store for the value and has a timestamp that is used to differentiate the valid content from stale ones.

According to the CAP theorem, distributed data stores cannot guarantee consistency, as availability and partition tolerance are more important issues.

Some data stores, like Riak, may use the more sophisticated vector clock instead of the timestamp to resolve stale information.

This is not the case in distributed data stores, where the concept of a table only vaguely exists.