How is the serial consistency level configured?

Serial consistency levels in the DataStax Distribution of Apache Cassandra 3.11 can be configured to manage lightweight transaction isolation.

Serial consistency levels in the DataStax Distribution of Apache Cassandra™ (DDAC) can be configured to manage lightweight transaction isolation. Lightweight transactions have two consistency levels defined. The SERIAL consistency level defines the serial consistency level for Paxos consensus of lightweight transactions. The learn phase uses a normal consistency level to define which read operations will be guaranteed to complete immediately if lightweight writes are occurring. The SERIAL consistency level is ignored for any query that is not a conditional update.

Serial consistency levels

Table 1. Serial Consistency Levels
Level Description Usage
SERIAL Achieves linearizable consistency for lightweight transactions by preventing unconditional updates. This consistency level is for use only with lightweight transaction. Equivalent to QUORUM.
LOCAL_SERIAL Same as SERIAL but confined to a single datacenter. A conditional write must be written to the commit log and memtable on a quorum of replica nodes in the same datacenter. Same as SERIAL but used to maintain consistency locally (within the single datacenter). Equivalent to LOCAL_QUORUM.