写操作
级别内容ZEROEnsure nothing. A write happens asynchronously in backgroundANY(Requires 0.6) Ensure that the write has been written to at least 1 node, including hinted recipients.ONEEnsure that the write has been written to at least 1 node's commit log and memory table before responding to the client.QUORUMEnsure that the write has been written to <Replication> / 2 + 1 nodes before responding to the client.ALLEnsure that the write is written to all <Replication> nodes before responding to the client. Any unresponsive nodes will fail the operation.
读操作
级别内容ZERONot supported, because it doesn't make sense.ANYNot supported. You probably want ONE instead.ONEWill return the record returned by the first node to respond. A co
nsistency check is always done in a background thread to fix any consistency issues when ConsistencyLevel.ONE is used. This means subsequent calls will have correct data even if the
initial read gets an older ">value. (This is called read repair .)QUORUMWill query all nodes and return the record with the
most recent timestamp once it has at least a majority of replicas reported. Again, the remaining replicas will be checked in the background.ALLWill query all nodes and return the record with the most recent timestamp once all nodes have replied. Any unresponsive nodes will fail the operation.