Batch statements are used to execute a series of simple or prepared statements.
There are 3 types of batch statements:
Cassandra::BATCH_LOGGED- this is the default batch type. This batch guarantees that either all or none of its statements will be executed. This behavior is achieved by writing a batch log on the coordinator, which slows down the execution somewhat.
Cassandra::BATCH_UNLOGGED- this batch will not be verified when executed, which makes it faster than a
LOGGEDbatch, but means that some of its statements might fail, while others - succeed.
Cassandra::BATCH_COUNTER- this batch is used for counter updates, which are, unlike other writes, not idempotent.