Specialized queries

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Specialized queries

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This group contains queries which do not fit into the other groups:

more_like_this query
This query finds documents which are similar to the specified text, document, or collection of documents.
script query
This query allows a script to act as a filter. Also see the function_score query.
percolate query
This query finds percolator queries based on documents.

More Like This Query (mlt)

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See: * More Like This Query

String[] fields = {"name.first", "name.last"};                 
String[] texts = {"text like this one"};                       
Item[] items = null;

QueryBuilder qb = moreLikeThisQuery(fields, texts, items)
    .minTermFreq(1)                                            
    .maxQueryTerms(12);                                        

fields

text

ignore threshold

max num of Terms in generated queries

Script Query

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See Script Query

QueryBuilder qb = scriptQuery(
    new Script("doc['num1'].value > 1") 
);

inlined script

If you have stored on each data node a script named myscript.painless with:

doc['num1'].value > params.param1

You can use it then with:

QueryBuilder qb = scriptQuery(
    new Script(
        "myscript",                            
        ScriptType.FILE,                       
        "painless",                            
        Collections.singletonMap("param1", 5)) 
);

Script name

Script type: either ScriptType.FILE, ScriptType.INLINE or ScriptType.INDEXED

Scripting engine

Parameters as a Map of <String, Object>

Percolate Query

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See: * Percolate Query

Settings settings = Settings.builder().put("cluster.name", "elasticsearch").build();
TransportClient client = new PreBuiltTransportClient(settings);
client.addTransportAddress(new InetSocketTransportAddress(new InetSocketAddress(InetAddresses.forString("127.0.0.1"), 9300)));

Before the percolate query can be used an percolator mapping should be added and a document containing a percolator query should be indexed:

// create an index with a percolator field with the name 'query':
client.admin().indices().prepareCreate("myIndexName")
                        .addMapping("query", "query", "type=percolator")
                        .addMapping("docs", "content", "type=text")
                        .get();

//This is the query we're registering in the percolator
QueryBuilder qb = termQuery("content", "amazing");

//Index the query = register it in the percolator
client.prepareIndex("myIndexName", "query", "myDesignatedQueryName")
    .setSource(jsonBuilder()
        .startObject()
            .field("query", qb) // Register the query
        .endObject())
    .setRefreshPolicy(RefreshPolicy.IMMEDIATE) // Needed when the query shall be available immediately
    .get();

This indexes the above term query under the name myDesignatedQueryName.

In order to check a document against the registered queries, use this code:

//Build a document to check against the percolator
XContentBuilder docBuilder = XContentFactory.jsonBuilder().startObject();
docBuilder.field("content", "This is amazing!");
docBuilder.endObject(); //End of the JSON root object

PercolateQueryBuilder percolateQuery = new PercolateQueryBuilder("query", "docs", docBuilder.bytes());

// Percolate, by executing the percolator query in the query dsl:
SearchResponse response = client().prepareSearch("myIndexName")
        .setQuery(percolateQuery))
        .get();
//Iterate over the results
for(SearchHit hit : response.getHits()) {
    // Percolator queries as hit
}