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Index Lifecycle

JanusGraph uses only indexes which have status ENABLED. When the index is created it will not be used by JanusGraph until it is enabled. After the index is build you should wait until it is registered (i.e. available) by JanusGraph: 

//Wait for the index to become available (i.e. wait for status REGISTERED)
ManagementSystem.awaitGraphIndexStatus(graph, "myIndex").call();

After the index is registered we should either enable the index (if we are sure that the current data should not be indexed by the newly created index) or we should reindex current data so that it would be available in the newly created index.

Reindex the existing data and automatically enable the index example: 

mgmt = graph.openManagement();
mgmt.updateIndex(mgmt.getGraphIndex("myIndex"), SchemaAction.REINDEX).get();
mgmt.commit();

Enable the index without reindexing existing data example: 

mgmt = graph.openManagement();
mgmt.updateIndex(mgmt.getGraphIndex("myAnotherIndex"), SchemaAction.ENABLE_INDEX).get();
mgmt.commit();

Index states and transitions

States and transitions

States (SchemaStatus)

An index can be in one of the following states:

  • INSTALLED The index is installed in the system but not yet registered with all instances in the cluster

  • REGISTERED The index is registered with all instances in the cluster but not (yet) enabled

  • ENABLED The index is enabled and in use

  • DISABLED The index is disabled and no longer in use

Actions (SchemaAction)

The following actions can be performed on an index to change its state via mgmt.updateIndex():

  • REGISTER_INDEX Registers the index with all instances in the graph cluster. After an index is installed, it must be registered with all graph instances

  • REINDEX Re-builds the index from the graph

  • ENABLE_INDEX Enables the index so that it can be used by the query processing engine. An index must be registered before it can be enabled.

  • DISABLE_INDEX Disables the index in the graph so that it is no longer used.

  • REMOVE_INDEX Removes the index from the graph (optional operation). Only on composite index.