Cassandra

CAP Theorem

• Consistency: All nodes see the same data at the same time
• Availability: Every request receives a response about whether it succeeded or failed
• Partition tolerance: The system continues to operate despite arbitrary partitioning due to network failures

The CAP theorem says that a system cannot provide all three.

Terms

CQL

Cassandra Query Language.

Replication factor

Number of copies of a piece of data

Keyspace

outer most container

Column Family

Like a table

CQL

 CREATE KEYSPACE Keyspace name
 WITH replication = {'class': 'SimpleStrategy', 'replication_factor' : 3};