Distributed Query Querying in Collections and Arrays Indexing in Collections and Arrays

You can also create an index using a query in collections and arrays.

Please note that in order to leverage the index, the attribute name used in the query has to be the same as the one used in the index definition.

Let's assume you have the following index definition:

<indexes>
  <index ordered="false">wheels[any].name</index>
</indexes>

The following query will use the index:

Predicate p = Predicates.equal('wheels[any].name', 'front-wheel');

The following query, however, will NOT leverage the index, since it does not use exactly the same attribute name that was used in the index:

Predicates.equal('wheels[0].name', 'front-wheel')

In order to use the index in the case mentioned above, you have to create another index, as shown below:

<indexes>
  <index ordered="false">wheels[0].name</index>
</indexes>