final QueryBuilder firstNestedQuery = QueryBuilders.nestedQuery( The nested query searches nested field objects as if they were indexed as separate documents. We have to find recipes having cheese as the main ingredient (weight less than 200) with two other ingredients: tomato (weight less than 100) and mushroom (weight greater than 50). Let’s say that this is the type of data we have stored on the Elasticsearch index: The nested type is a specialized version of the object data type that allows arrays of objects to be indexed such that they can be queried independently of each other. Elasticsearch has no concept of inner objects. To run a nested query, you must have an index that includes nested mapping. Boolean operations with the Bool Query Fields analogy Using nested query with nested object mustNot(QueryBuilders.termQuery(field2, value3)) įinal BoolQueryBuilder filter = new BoolQueryBuilder() must(QueryBuilders.termQuery(field1, value3)) must(QueryBuilders.termQuery(field2, value2)) įinal BoolQueryBuilder second = QueryBuilders.boolQuery() must(QueryBuilders.termQuery(field1, value1)) GET index/_searchįinal BoolQueryBuilder first = QueryBuilders.boolQuery() An example of logical expressionĮlasticsearch provides the facility for combining these queries using the bool query (one of the compound query clauses). For the sake of simplicity and readability, this expression is divided into three parts.įigure 1. Now, let’s convert a more complex logical expression into a QueryBuilder object. The AND/OR/NOT operators can be used to fine-tune search queries to provide more relevant or specific results. final QueryBuilder rangeQuery = QueryBuildersįinal QueryBuilder rangeQuery = QueryBuilders To find the objects having values between the ranges of given values, we can use the rangeQuery parameter followed by the field and the conditions to check. To search for the exact term you provide, use the term query. Keep in mind that Elasticsearch will analyze the text field lowercase unless you define a custom mapping. Converting the above Elasticsearch query in JSON format to a QueryBuilder object will give the following: final QueryBuilder qb = QueryBuilders.matchQuery("name", "Pizza") īoth the Elasticsearch query and the query written using Querybuilders class will return all the documents with the name “Pizza.” The match query also analyzes provided search term before performing a search. The QueryBuilders class provides a variety of static methods used as dynamic matchers to find specific entries in the cluster. We can use this query to search for text, numbers, or boolean values. The “match” query is one of the most basic and commonly used queries in Elasticsearch and functions as a full-text query. Essentially, they combine multiple queries to achieve their target results. Compound queries use the combination of leaf or compound queries. Some of these queries include match, term, and range queries. Leaf queries search for specific values in a certain field (or fields) and can be used independently. The queries in Elasticsearch can be broadly classified into leaf and compound queries. In this Tech Bite, we will see how to use ElasticSearch’s Java API to perform some of the common Elasticsearch queries.
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