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## 5.7. Search

An index can be searched in two ways, get and query. The `get` method will return exact matches to the given key-value pair, whereas `query` exposes querying capabilities directly from the backend used by the index. For example the Lucene query syntax can be used directly with the default indexing backend.

### 5.7.1. Get

This is how to search for a single exact match:

    IndexHits<Node> hits = actors.get( "name", "Keanu Reeves" );
    Node reeves = hits.getSingle();

IndexHits is an `Iterable` with some additional useful methods. For example getSingle() returns the first and only item from the result iterator, or `null` if there isn’t any hit.

Here’s how to get a single relationship by exact matching and retrieve its start and end nodes:

    Relationship persephone = roles.get( "name", "Persephone" ).getSingle();
    Node actor = persephone.getStartNode();
    Node movie = persephone.getEndNode();

Finally, we can iterate over all exact matches from a relationship index:

    for ( Relationship role : roles.get( "name", "Neo" ) )
    {
        // this will give us Reeves twice
        Node reeves = role.getStartNode();
    }

| Important
In you don’t iterate through all the hits, IndexHits.close() must be called explicitly.

### 5.7.2. Query

There are two query methods, one which uses a key-value signature where the value represents a query for values with the given key only. The other method is more generic and supports querying for more than one key-value pair in the same query.

Here’s an example using the key-query option:

    for ( Node actor : actors.query( "name", "*e*" ) )
    {
        // This will return Reeves and Bellucci
    }

In the following example the query uses multiple keys:

    for ( Node movie : movies.query( "title:*Matrix* AND year:1999" ) )
    {
        // This will return "The Matrix" from 1999 only.
    }

| Note
Beginning a wildcard search with "*" or "?" is discouraged by Lucene, but will nevertheless work.

| Caution
You can’t have any whitespace in the search term with this syntax. See Section 5.11.3, “Querying with Lucene Query objects” for how to do that.

Copyright © 2011 Neo Technology

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