Hi Marc,
IMHO, an index should not prevent a query to work. Moreover the result of a query should not depends of backends (storage and index). If an index backend cannot process a predicate, the predicate should be be executed as if index wasn't present.
To clarify, below is a sample of code. The same query works without index (line 13) and fails with index (line 31).
1 // create schema
2 mgmt = graph.openManagement()
3 mgmt.makePropertyKey('string').dataType(String.class).cardinality(Cardinality.SINGLE).make()
4 mgmt.makeVertexLabel('data').make()
5 mgmt.commit()
6
7 // add data
8 g.addV('data').property('string', 'foo')
9 ==>v[4120]
10 g.addV('data').property('string', 'bar')
11 ==>v[4312]
12
13 g.V().hasLabel('data').has('string', textNotContains('bar'))
14 WARN org.janusgraph.graphdb.transaction.StandardJanusGraphTx - Query requires iterating over all vertices [(~label = data AND string textNotContains bar)]. For better performance, use indexes
15 ==>v[4120]
16
17 // add indexe with lucene backend
18 mgmt = graph.openManagement()
19 string = mgmt.getPropertyKey("string")
20 mgmt.buildIndex('myindex', Vertex.class).addKey(string, Mapping.TEXTSTRING.asParameter()).buildMixedIndex("search")
21 mgmt.commit()
22
23 // Wait the indexes
24 ManagementSystem.awaitGraphIndexStatus(graph, 'myindex').call()
25
26 // Reindex data
27 mgmt = graph.openManagement()
28 mgmt.updateIndex(mgmt.getGraphIndex("myindex"), SchemaAction.REINDEX).get()
29 mgmt.commit()
30
31 g.V().hasLabel('data').has('string', textNotContains('bar'))
32 Could not call index
Regards,
Toom.
