I'm finally getting the hang of Cassandra, part of the issue was learning / respecting the differences between Thrift and CQL3.
Many of the tutorials I am finding online are for CQL3. My question: Is CQL3 truly the preferred method, and is Thrift being discouraged? Reason I ask is I spent a couple of days trying to get what I needed through Pycassa which does not support Cassandra 1.2 and that is based on the Thrift model.
Is CQL3 truly the preferred method, and is Thrift being discouraged?
Short answer is yes.
Longer answer is:
CQL3 should be preferred for many reasons:
platform-agnostic language: CQL3 looks like SQL and is easier to handle that pure Thrift API code.
Higher level of abstraction: for end-users, it's easier to deal with CQL3 to query data rather than juggling with low-level Thrift API, although some good higher abstraction frameworks exist (Hector for Java, Pycassa for Python ...=
Easier to administer for operational teams: when creating a new table or adding new referential data, it is easier to write CQL3 scripts that ops teams can understand, check and execute rather than cryptic cassandra-cli scripts (set cf[rowKey][columnName] = ...). I'm migrating all our cassandra-cli scripts to CQL3 because it's a pain in the ass to maintain them
Last but not least, CQL3 make life easier for third-party framework developers. I've developed Achilles, an open-source persistence manager for Cassandra. The Thrift version was painfull to implement, the CQL3 version was a piece of cake escpecially because it uses the Java Driver from Datastax
That being said, CQL3 is no bed of roses either. Before leveraging the full power of the query language, you need to understand how Cassandra storage engine works. The language gives you the illusion that everything is easy and will work as SQL but the plain truth is no. There are some important semantics differences, especially when using the WHERE clause.