目录
1、背景
我有一堆学生数据，其中湖北省的学生需要排在所有数据的最前面。其余省正序排序，对于同一个省的数据，按照年龄倒序排序。
2、分析
对于上方的排序需求，湖北省的学生数据需要排在前端，但是湖北省并不是一个字段，那么这个时候改如何实现呢？对于这种场景我们很容易就想到需要脚本script sort来实现。
3、构建数据
3.1 mapping
PUT /index_person { "settings": { "number_of_shards": 1 }, "mappings": { "properties": { "id":{ "type": "long" }, "name": { "type": "keyword" }, "age": { "type": "integer" }, "province":{ "type": "keyword" } } } } 3.2 插入数据
PUT /index_person/_bulk {"index":{"_id":1}} {"id":1, "name":"张三","age":18,"province":"湖北"} {"index":{"_id":2}} {"id":2, "name":"李四","age":19,"province":"湖北"} {"index":{"_id":3}} {"id":3, "name":"王武","age":20,"province":"西安"} {"index":{"_id":4}} {"id":4, "name":"赵六","age":21,"province":"西安"} {"index":{"_id":5}} {"id":5, "name":"钱七","age":22,"province":"上海"} 4、实现
4.1 根据省升序排序
4.1.1 dsl
GET index_person/_search { "query": { "match_all": {} }, "sort": [ { "province": { "order": "asc" } } ] } 4.1.2 运行结果
可以看到省升序的排序顺序为 上海、湖北、西安。
4.2 湖北省排第一
4.2.1 dsl
GET index_person/_search { "query": { "match_all": {} }, "sort": [ { "_script": { "type": "number", "order": "desc", "script": { "lang": "painless", "source": """ if(params['_source']['province'] == '湖北'){ 1 } else { 0 } """ } } } ] } 4.2.2 运行结果
通过如上的 script sort排序之后，就可以看到 湖北省已经是排到第一位了。
4.3 湖北省排第一，其余省升序排序，按照年龄倒序
4.3.1 dsl
GET index_person/_search { "query": { "match_all": {} }, "sort": [ { "_script": { "type": "number", "order": "desc", "script": { "lang": "painless", "source": """ if(params['_source']['province'] == '湖北'){ 1 } else { 0 } """ } } }, { "province": { "order": "asc" }, "age": { "order": "desc", "missing": "_last" } } ] } 4.3.2 java代码
@Test @DisplayName("脚本排序，固定的某个值的数据排在前面，其余的数据按照别的字段排序") public void test01() throws IOException { SearchRequest request = SearchRequest.of(searchRequest -> searchRequest.index("index_person") .query(query -> query.matchAll(matchAll -> matchAll)) .size(100) .sort(sort -> sort.script(sortScript -> sortScript.type(ScriptSortType.Number) .order(SortOrder.Desc) .script(script -> script.inline(inline -> inline.source("if(params['_source']['province'] == params.province){n" + " 1n" + " } else {n" + " 0n" + " }") .params("province", JsonData.of("湖北")) ) ) ) ) .sort(sort -> sort.field(field -> field.field("province").order(SortOrder.Asc) ) ) .sort(sort -> sort.field(field -> field.field("age").order(SortOrder.Desc).missing("_last") ) ) ); System.out.println("request: " + request); SearchResponse<Object> response = client.search(request, Object.class); System.out.println("response: " + response); } 4.3.3 运行结果
5、完整代码
6、参考文档
1、https://www.elastic.co/guide/en/elasticsearch/reference/7.17/sort-search-results.html
