Database Reference
In-Depth Information
Summary
Having spent the bulk of this topic exploring Cassandra using CQL, we've now peeked un-
der the hood to see how the robust data structures offered by CQL are in fact abstractions
upon a much more rudimentary column family data structure. If nothing else, this is an op-
portunity to appreciate modern technology; as recently as Cassandra 1.1, the CQL data
structures we take for granted were unheard of. Before Cassandra 0.7, CQL did not exist at
all; the Thrift interface we explored in this chapter was state-of-the-art.
Our deep dive into Cassandra's internal data structures also helps us understand the under-
lying reasons behind facts that in previous chapters we'd taken as first principles. You
learned in
Chapter 3
,
Organizing Related Data
that partition keys group related data, but
now we know that in fact all the data under a partition key, or
RowKey
, coexists in a single
wide row. Similarly, we already knew that clustering columns determine row ordering, but
now we know that the sorting is actually happening to cells in a wide row, and the use of
the clustering column as a prefix for wide row cell names generates the familiar behavior at
the CQL level.
In the final appendix, we will do a brief survey of Cassandra's authentication and authoriza-
tion functionality, and discuss the various tools Cassandra gives you for protecting your de-
ployments against security vulnerabilities.
