欢迎投稿

今日深度:

Elasticsearch Aggregation 多个字段分组统计 Java API实现,

Elasticsearch Aggregation 多个字段分组统计 Java API实现,


Elasticsearch Aggregation 多个字段分组统计 Java API实现

现有索引数据:

index:school

type:student

---------------------------------------------------

{"grade":"1", "class":"1", "name":"xiao 1"}

{"grade":"1", "class":"1", "name":"xiao 2"}

{"grade":"1", "class":"2", "name":"xiao 3"}

{"grade":"1", "class":"2", "name":"xiao 4"}

{"grade":"1", "class":"2", "name":"xiao 5"}

?

Java分组统计年级和班级学生个数,如SQL: SELECT grade,class,count(1) FROM student GROUP BY grade,class;

?

package test;

?

import java.util.Iterator;

import java.util.Map;

?

import org.elasticsearch.action.search.SearchRequestBuilder;

import org.elasticsearch.action.search.SearchResponse;

import org.elasticsearch.action.search.SearchType;

import org.elasticsearch.search.aggregations.Aggregation;

import org.elasticsearch.search.aggregations.AggregationBuilders;

import org.elasticsearch.search.aggregations.bucket.terms.StringTerms;

import org.elasticsearch.search.aggregations.bucket.terms.Terms.Bucket;

import org.elasticsearch.search.aggregations.bucket.terms.TermsBuilder;

import org.junit.Test;

?

import utils.NesUtils;

?

public class TestAggregation

{

@Test

public void testAggregation()

{

SearchRequestBuilder srb = NesUtils.getSearcher("school");

srb.setTypes("student");

srb.setSearchType(SearchType.COUNT);

?

TermsBuilder gradeTermsBuilder = AggregationBuilders.terms("gradeAgg").field("grade");

TermsBuilder classTermsBuilder = AggregationBuilders.terms("classAgg").field("class");

?

gradeTermsBuilder.subAggregation(classTermsBuilder);

?

srb.addAggregation(gradeTermsBuilder);

?

SearchResponse sr = srb.execute().actionGet();

?

Map aggMap = sr.getAggregations().asMap();

?

StringTerms gradeTerms = (StringTerms) aggMap.get("gradeAgg");

?

Iterator gradeBucketIt = gradeTerms.getBuckets().iterator();

?

while(gradeBucketIt.hasNext())

{

Bucket gradeBucket = gradeBucketIt.next();

System.out.println(gradeBucket.getKey() + "年级有" + gradeBucket.getDocCount() +"个学生。");

?

StringTerms classTerms = (StringTerms) gradeBucket.getAggregations().asMap().get("classAgg");

Iterator classBucketIt = classTerms.getBuckets().iterator();

?

while(classBucketIt.hasNext())

{

Bucket classBucket = classBucketIt.next();

System.out.println(gradeBucket.getKey() + "年级" +classBucket.getKey() + "班有" + classBucket.getDocCount() +"个学生。");

}

System.out.println();

}

?

}

}

运行完成输出结果

---------------------------------------------------

1年级有5个学生。

1年级2班有3个学生。

1年级1班有2个学生。


www.htsjk.Com true http://www.htsjk.com/Elasticsearch/36090.html NewsArticle Elasticsearch Aggregation 多个字段分组统计 Java API实现, Elasticsearch Aggregation 多个字段分组统计 Java API实现 现有索引数据: index:school type:student --------------------------------------------------- {"gra...
相关文章
    暂无相关文章
评论暂时关闭