Jc Gibson wrote:But the O(1) mechanism is not rows and tables.
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Firstly, please check HowToAskQuestionsOnJavaRanch. I'm not getting what your exact question is. Is it about Cassandra being better than relational database? Or other way round? Or is it about why asymptotic notation is used for database?
Also, please CarefullyChooseOneForum. I really doubt whether Cassandra has anything to do with EJB certification.