java实现Elasticsearch去重统计数量
时间: 2023-06-29 15:19:30 浏览: 130
Java操作Elasticsearch
在Java中实现ES的去重统计数量可以使用ES的Java客户端库。下面是一个示例代码:
```
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RequestOptions;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.search.aggregations.AggregationBuilders;
import org.elasticsearch.search.aggregations.metrics.cardinality.Cardinality;
import org.elasticsearch.search.aggregations.metrics.cardinality.CardinalityAggregationBuilder;
import org.elasticsearch.search.builder.SearchSourceBuilder;
public class EsDeduplication {
public static long getDeduplicatedCount(RestHighLevelClient client, String index, String field) throws IOException {
SearchRequest searchRequest = new SearchRequest(index);
SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();
searchSourceBuilder.query(QueryBuilders.matchAllQuery());
CardinalityAggregationBuilder aggregationBuilder = AggregationBuilders.cardinality("deduplicated_count").field(field);
searchSourceBuilder.aggregation(aggregationBuilder);
searchRequest.source(searchSourceBuilder);
SearchResponse searchResponse = client.search(searchRequest, RequestOptions.DEFAULT);
Cardinality cardinality = searchResponse.getAggregations().get("deduplicated_count");
return cardinality.getValue();
}
}
```
在这个代码中,我们创建了一个名为`getDeduplicatedCount`的方法,该方法接受ES客户端、索引名和要去重的字段名作为参数。该方法首先创建一个`SearchRequest`对象,并使用`SearchSourceBuilder`对象构建了一个查询。查询使用`matchAllQuery`来匹配所有文档,并使用`CardinalityAggregationBuilder`聚合函数来对指定字段进行去重统计。聚合结果中的`deduplicated_count`桶中包含去重后的数量,并通过`getValue`方法获取该值。
在代码中,我们使用了ES的Java客户端库,因此需要将该库添加到项目的依赖中。您可以根据您的ES版本和其他要求选择正确的版本。
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