Apache Cassandra is a free open source distributed wide column store initially developed by Facebook.
Cassandra is master less – no need to define master node, every node writes and reads its local shard data bringing best high availability and speed .
Cassandra belong to the NoSQL family but has CQL (SQL Like ) Interface which enable you to create tables , primary keys , cluster indexes and write “SQL” to insert and select data .Cassandra Distribute the data between the nodes according to the primary key values thus load balance the read /writes requests between the nodes evenly .
The fact that Cassandra has cluster indexes enables the application to retrieve data very fast by key value but also to make a very fast drill down to the cluster index columns which is not available in other NoSQL databases.
Cassandra supports scale out by adding nodes and high availability using replication between the nodes.
Cassandra can support 1 million operations per second and very heavy read write operations in real time.
Application types: Social networks, Time series, IOT, session management.
MySQL Galera Cluster Introduction MySQL Galera cluster is the common solution for MySQL high availability and bring