Session: How to Use MoreLikeThis
MoreLikeThis is available through query methods and will return similar documents according to the provided criteria and options.
Syntax
IDocumentQuery<T> moreLikeThis(MoreLikeThisBase moreLikeThis);
IDocumentQuery<T> moreLikeThis(Consumer<IMoreLikeThisBuilderForDocumentQuery<T>> builder);
| Parameters |
|
|
| moreLikeThis |
MoreLikeThisBase |
Defines the type of MoreLikeThis that should be executed |
| builder |
Consumer<IMoreLikeThisBuilderForDocumentQuery<T>> |
Builder with fluent API that constructs the MoreLikeThisBase instance |
Builder
IMoreLikeThisOperations<T> usingAnyDocument();
IMoreLikeThisOperations<T> usingDocument(String documentJson);
IMoreLikeThisOperations<T> usingDocument(Consumer<IFilterDocumentQueryBase<T, IDocumentQuery<T>>> builder);
IMoreLikeThisOperations<T> withOptions(MoreLikeThisOptions options);
| Parameters |
|
|
| documentJson |
String |
Inline JSON document that will be used as a base for operation |
| builder |
Consumer<IFilterDocumentQueryBase<T, IDocumentQuery<T>>> |
Filtering expression utilized to find a document that will be used as a base for operation |
| options |
MoreLikeThisOptions |
Non-default options that should be used for operation |
Options
private Integer minimumTermFrequency = 2;
private Integer maximumQueryTerms = 25;
private Integer maximumNumberOfTokensParsed = 5000;
private Integer minimumWordLength = 0;
private Integer maximumWordLength = 0;
private Integer minimumDocumentFrequency = 5;
private Integer maximumDocumentFrequency = Integer.MAX_VALUE;
private Integer maximumDocumentFrequencyPercentage;
private Boolean boost = false;
private Float boostFactor = 1f;
private String stopWordsDocumentId;
private String[] fields;
// getters and setters
| Options |
|
|
| MinimumTermFrequency |
Integer |
Ignores terms with less than this frequency in the source doc |
| MaximumQueryTerms |
Integer |
Returns a query with no more than this many terms |
| MaximumNumberOfTokensParsed |
Integer |
The maximum number of tokens to parse in each example doc field that is not stored with TermVector support |
| MinimumWordLength |
Integer |
Ignores words less than this length or, if 0, then this has no effect |
| MaximumWordLength |
Integer |
Ignores words greater than this length or if 0 then this has no effect |
| MinimumDocumentFrequency |
Integer |
Ignores words which do not occur in at least this many documents |
| MaximumDocumentFrequency |
Integer |
Ignores words which occur in more than this many documents |
| MaximumDocumentFrequencyPercentage |
Integer |
Ignores words which occur in more than this percentage of documents |
| Boost |
Boolean |
Boost terms in query based on score |
| BoostFactor |
Float |
Boost factor when boosting based on score |
| StopWordsDocumentId |
String |
Document ID containing custom stop words |
| Fields |
String[] |
Fields to compare |
Example I
// Search for similar articles to 'articles/1'
// using 'Articles/MoreLikeThis' index and search only field 'body'
MoreLikeThisOptions options = new MoreLikeThisOptions();
options.setFields(new String[]{ "body" });
List<Article> articles = session
.query(Article.class, Query.index("Articles/MoreLikeThis"))
.moreLikeThis(builder -> builder
.usingDocument(x -> x.whereEquals("id()", "articles/1"))
.withOptions(options))
.toList();
from index 'Articles/MoreLikeThis'
where morelikethis(id() = 'articles/1', '{ "Fields" : [ "body" ] }')
Example II
// Search for similar articles to 'articles/1'
// using 'Articles/MoreLikeThis' index and search only field 'body'
// where article category is 'IT'
MoreLikeThisOptions options = new MoreLikeThisOptions();
options.setFields(new String[]{ "body" });
List<Article> articles = session
.query(Article.class, Query.index("Articles/MoreLikeThis"))
.moreLikeThis(builder -> builder
.usingDocument(x -> x.whereEquals("id()", "articles/1"))
.withOptions(options))
.whereEquals("category", "IT")
.toList();
from index 'Articles/MoreLikeThis'
where morelikethis(id() = 'articles/1', '{ "Fields" : [ "body" ] }') and category == 'IT'