如何定制搜索结果的排序规则

如何将一个field索引两次来解决字符串排序问题

如果对一个string field进行排序，结果往往不准确，因为分词后是多个单词，再排序就不是我们想要的结果了

通常解决方案是，将一个string field建立两次索引，一个分词，用来进行搜索；一个不分词，用来进行排序

1.设置索引类型

PUT /website
{
“mappings”: {
​ “article”: {
​ “properties”: {
​ “title”: {
​ “type”: “text”,
​ “fields”: {
​ “raw”: {// 一般会用raw来表示
​ “type”: “string”,
​ “index”: “not_analyzed”
​ }
​ },
​ “fielddata”: true // 涉及正排索引
​ },
​ “content”: {
​ “type”: “text”
​ },
​ “post_date”: {
​ “type”: “date”
​ },
​ “author_id”: {
​ “type”: “long”
​ }
​ }
​ }
}
}

2. 添加数据

PUT /website/article/1
{
“title”: “first article”,
“content”: “this is my second article”,
“post_date”: “2017-01-01”,
“author_id”: 110
}

GET /website/article/_search

{
“took”: 2,
“timed_out”: false,
“_shards”: {
​ “total”: 5,
​ “successful”: 5,
​ “failed”: 0
},
“hits”: {
​ “total”: 3,
​ “max_score”: 1,
​ “hits”: [
​ {
​ “_index”: “website”,
​ “_type”: “article”,
​ “_id”: “2”,
​ “_score”: 1,
​ “_source”: {
​ “title”: “first article”,
​ “content”: “this is my first article”,
​ “post_date”: “2017-02-01”,
​ “author_id”: 110
​ }
​ },
​ {
​ “_index”: “website”,
​ “_type”: “article”,
​ “_id”: “1”,
​ “_score”: 1,
​ “_source”: {
​ “title”: “second article”,
​ “content”: “this is my second article”,
​ “post_date”: “2017-01-01”,
​ “author_id”: 110
​ }
​ },
​ {
​ “_index”: “website”,
​ “_type”: “article”,
​ “_id”: “3”,
​ “_score”: 1,
​ “_source”: {
​ “title”: “third article”,
​ “content”: “this is my third article”,
​ “post_date”: “2017-03-01”,
​ “author_id”: 110
​ }
​ }
​ ]
}
}

3. 使用不分词的索引字段进行排序

GET /website/article/_search
{
“query”: {
​ “match_all”: {}
},
“sort”: [
​ {
​ “title.raw”: {
​ “order”: “desc”
​ }
​ }
]
}