How to: AP database
An AP database delivers availability and partition tolerance at the expense of consistency. When a partition occurs, all nodes remain available but those at the wrong end of a partition might return an older version of data than others. When the partition is resolved, the AP databases typically re-syncs the nodes to repair all inconsistencies in the system.

**Example**: [Apache Cassandra](https://cassandra.apache.org), [CouchDB](https://couchdb.apache.org).