The Cassandra Query Language (CQL) is a query language for the ScyllaDB database. CQL shell (CQLSH) is the primary tool for interacting with the database. The lesson includes some example commands and where to look for more information.
Transcript
CQL,monitoring so the CQL shell is the easiest most common it’s like
the first door that you open when you start using ScyllaDB because it’s
great you get your packages you install, you run ScyllaDB set up
ScyllaDB is working and then what’s next you want to create a key space you want
to create a table you want to insert some data usually people do that with
CQL and/or they use for example whatever programming language that they love you
can we have drivers and connectors for pretty much everything but CQL is a good
way to prototype to you know get a feel if you’re new to ScyllaDB or
anything like NOCQL or Cassandra so you can explore a little bit these are
you know some of the options. CQL usually is
interactive so you run CQLSH and then you start typing commands so
you can describe key spaces tables you can check the consistency that
CQL is using by default I think it’s consistency level of one but you can
change to quorum, local quorum, all whatever and use the help page of course these
are more options this one I want you to pay attention because “-e” is to
avoid interactive mode so I just wanted to describe my schema I use
CQL -e desk schema it will give an output I can pipe that into
a file send it to the ScyllaDB team and “-f” let’s say you have you know 200 inserts
you want to do put it on a file -f file it’s going to run all those
CQL statements inside the file so -f for a file – e to avoid
interactive mode so again control the environment docker docker developed
dev environment whatever don’t run things in production first, just going
back here you can set the timeout let’s say you are doing a select star from
table you have 2 million records it’s not going to finish in you know five
seconds running on your docker so increase the timeout if you’re doing
something like that but by all means don’t plan your queries for you know big
times right one of the reasons you’re using ScyllaDB you want it to be fast
so try to design your queries accordingly – e – f by all means have fun I
had a lot of fun when I joined ScyllaDB. I didn’t know anything about CQL it took
me like two days he’s just playing around and I was
already familiar with it for more complex environments and simulations
don’t use CQLSH you want to experiment with replication factor, consistency
level you want to see latencies you want to ingest a lot of data CQL is not
for that SQL is for you know very specific stuff and playing around if you
want to do simulation by all means use something like Cassandra stress or
create some code in your favorite language
