H2
H2 is an embedded database that is pre-configured in the default nifi-registry.properties file. The contents of the H2 database are stored in a file on the local filesystem.
For NiFi Registry 0.1.0, the location of the H2 database is specified by the property:
nifi.registry.db.directory=./database
For NiFi Registry 0.2.0 and forward, the location of the H2 database is specified as part of the JDBC URL property:
nifi.registry.db.url=jdbc:h2:./database/nifi-registry-primary;