背景
ES在查询时如果数量太多,而每行记录包含的字段很多,那就会导致超出ES的查询上线,默认是100MB,但是很多场景下我们只需要返回特定的字段即可,那么如何操作呢。
主要代码
@Autowired private RestHighLevelClient client; public List<Map<String,Object>> search(String index) { List<Map<String,Object>> hitList = new ArrayList(); try { //搜索请求 SearchRequest request = new SearchRequest(index); SearchSourceBuilder sourceBuilder = new SearchSourceBuilder(); BoolQueryBuilder boolQueryBuilder = QueryBuilders.boolQuery(); //查询某字段不为空 boolQueryBuilder.must(QueryBuilders.boolQuery().must((QueryBuilders.existsQuery("字段"+ ".keyword")))); //查询指定字段 String[] fields = {"字段1","字段2"}; sourceBuilder.fetchSource(fields,null); //把查询添加放入请求中 sourceBuilder.query(boolQueryBuilder); request.source(sourceBuilder); //查询数量 sourceBuilder.size(10000); sourceBuilder.trackTotalHits(true); //建立SearchResponse SearchResponse response; response = client.search(request, RequestOptions.DEFAULT); //封装查询的信息 for (SearchHit hit : response.getHits().getHits()) { hitList.add(hit.getSourceAsMap()); log.debug("查询结果:{}", hit.getSourceAsString()); } } catch (IOException e) { e.printStackTrace(); } return hitList; }
String[] fields = {“字段1”,“字段2”};
sourceBuilder.fetchSource(fields,null);
注意:字段不是实体类中的字段,而是表中的名称,不是userStatus而是user_status
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首发链接: https://www.cnblogs.com/lingyejun/p/17818598.html
标签:Java,String,fields,sourceBuilder,查询,字段,elasticsearch,hit From: https://www.cnblogs.com/lingyejun/p/17818598.html