6. What programming language is Cassandra written in and why does it matter?
Java
The primary reason is that it is the most transportable of the current
languages so that the software can be ported to many different systems.
But, Java does not produce the fastest executing code. (But it
is not too bad for most things.) In terms of installation, it means that
Cassandra can only be installed after the proper version of Java is
installed.
On a side note, the CQL interactive query processor is written in Python,
which is (a) even slower, and (b) needs to be installed on some
systems—particularly Windows.