elasticsearch group-by multiple fields

Question

I am Looking for the best way to group data in elasticsearch. Elasticsearch doesn\'t support something like \'group by\' in sql.

Lets say I have 1k categories and mi

Answer 1

I think some developers will be definitely looking same implementation in Spring DATA ES and JAVA ES API.

Please finds :-

List fieldObjectList = Lists.newArrayList();
    SearchQuery aSearchQuery = new NativeSearchQueryBuilder().withQuery(matchAllQuery()).withIndices(indexName).withTypes(type)
            .addAggregation(
                    terms("ByField1").field("field1").subAggregation(AggregationBuilders.terms("ByField2").field("field2")
                            .subAggregation(AggregationBuilders.terms("ByField3").field("field3")))
                    )
            .build();
    Aggregations aField1Aggregations = elasticsearchTemplate.query(aSearchQuery, new ResultsExtractor() {
        @Override
        public Aggregations extract(SearchResponse aResponse) {
            return aResponse.getAggregations();
        }
    });
    Terms aField1Terms = aField1Aggregations.get("ByField1");
    aField1Terms.getBuckets().stream().forEach(aField1Bucket -> {
        String field1Value = aField1Bucket.getKey();
        Terms aField2Terms = aField1Bucket.getAggregations().get("ByField2");

        aField2Terms.getBuckets().stream().forEach(aField2Bucket -> {
            String field2Value = aField2Bucket.getKey();
            Terms aField3Terms = aField2Bucket.getAggregations().get("ByField3");

            aField3Terms.getBuckets().stream().forEach(aField3Bucket -> {
                String field3Value = aField3Bucket.getKey();
                Long count = aField3Bucket.getDocCount();

                FieldObject fieldObject = new FieldObject();
                fieldObject.setField1(field1Value);
                fieldObject.setField2(field2Value);
                fieldObject.setField3(field3Value);
                fieldObject.setCount(count);
                fieldObjectList.add(fieldObject);
            });
        });
    });

imports need to be done for same :-

import static org.elasticsearch.index.query.QueryBuilders.matchAllQuery;
import static org.elasticsearch.search.aggregations.AggregationBuilders.terms; 
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.common.collect.Lists;
import org.elasticsearch.index.query.FilterBuilder;
import org.elasticsearch.index.query.FilterBuilders;
import org.elasticsearch.index.query.TermFilterBuilder;
import org.elasticsearch.search.aggregations.AggregationBuilders;
import org.elasticsearch.search.aggregations.Aggregations;
import org.elasticsearch.search.aggregations.bucket.filter.InternalFilter;
import org.elasticsearch.search.aggregations.bucket.terms.Terms;
import org.springframework.data.elasticsearch.core.ElasticsearchTemplate;
import org.springframework.data.elasticsearch.core.ResultsExtractor;
import org.springframework.data.elasticsearch.core.query.NativeSearchQueryBuilder;
import org.springframework.data.elasticsearch.core.query.SearchQuery;