文章目录
- 概述
- 官方文档
- 例子
- tie_breaker
概述
继续跟中华石杉老师学习ES，第十一篇
课程地址： https://www.roncoo.com/view/55
官方文档
https://www.elastic.co/guide/en/elasticsearch/guide/current/_tuning_best_fields_queries.html
https://www.elastic.co/guide/en/elasticsearch/reference/7.2/query-dsl-dis-max-query.html
例子
数据同 上篇博文 构造索引的DSL
这次我们使用dis_max查询 java beginner , DSL如下
代码语言：javascript复制GET /forum/article/_search
{
"query": {
"dis_max": {
"queries": [
{
"match": {
"title": "java beginner"
}
},
{
"match": {
"content": "java beginner"
}
}
]
}
}
}返回
代码语言：javascript复制{
"took": 2,
"timed_out": false,
"_shards": {
"total": 1,
"successful": 1,
"skipped": 0,
"failed": 0
},
"hits": {
"total": 5,
"max_score": 1.0341108,
"hits": [
{
"_index": "forum",
"_type": "article",
"_id": "3",
"_score": 1.0341108,
"_source": {
"articleID": "JODL-X-1937-#pV7",
"userID": 2,
"hidden": false,
"postDate": "2017-01-01",
"tag": [
"hadoop"
],
"tag_cnt": 1,
"view_cnt": 100,
"title": "this is elasticsearch blog",
"content": "i am only an elasticsearch beginner"
}
},
{
"_index": "forum",
"_type": "article",
"_id": "2",
"_score": 0.93952733,
"_source": {
"articleID": "KDKE-B-9947-#kL5",
"userID": 1,
"hidden": false,
"postDate": "2017-01-02",
"tag": [
"java"
],
"tag_cnt": 1,
"view_cnt": 50,
"title": "this is java blog",
"content": "i think java is the best programming language"
}
},
{
"_index": "forum",
"_type": "article",
"_id": "4",
"_score": 0.79423964,
"_source": {
"articleID": "QQPX-R-3956-#aD8",
"userID": 2,
"hidden": true,
"postDate": "2017-01-02",
"tag": [
"java",
"elasticsearch"
],
"tag_cnt": 2,
"view_cnt": 80,
"title": "this is java, elasticsearch, hadoop blog",
"content": "elasticsearch and hadoop are all very good solution, i am a beginner"
}
},
{
"_index": "forum",
"_type": "article",
"_id": "5",
"_score": 0.7116974,
"_source": {
"articleID": "DHJK-B-1395-#Ky5",
"userID": 3,
"hidden": false,
"postDate": "2019-05-01",
"tag": [
"elasticsearch"
],
"tag_cnt": 1,
"view_cnt": 10,
"title": "this is spark blog",
"content": "spark is best big data solution based on scala ,an programming language similar to java"
}
},
{
"_index": "forum",
"_type": "article",
"_id": "1",
"_score": 0.4889865,
"_source": {
"articleID": "XHDK-A-1293-#fJ3",
"userID": 1,
"hidden": false,
"postDate": "2017-01-01",
"tag": [
"java",
"hadoop"
],
"tag_cnt": 2,
"view_cnt": 30,
"title": "this is java and elasticsearch blog",
"content": "i like to write best elasticsearch article"
}
}
]
}
}
不知道为啥id=3的相关度是最高的… 如果有知道的，烦请不吝赐教。
dis_max只取某一个query最大的分数，完全不考虑其他query的分数
tie_breaker
使用tie_breaker将其他query的分数也考虑进去
tie_breaker参数的意义，在于说，将其他query的分数，乘以tie_breaker，然后综合与最高分数的那个query的分数，综合在一起进行计算，除了取最高分以外，还会考虑其他的query的分数。
tie_breaker的值，在0~1之间，是个小数。
代码语言：javascript复制GET /forum/article/_search
{
"query": {
"dis_max": {
"queries": [
{
"match": {
"title": "java beginner"
}
},
{
"match": {
"content": "java beginner"
}
}
],
"tie_breaker": 0.7
}
}
}返回结果
代码语言：javascript复制{
"took": 2,
"timed_out": false,
"_shards": {
"total": 1,
"successful": 1,
"skipped": 0,
"failed": 0
},
"hits": {
"total": 5,
"max_score": 1.344432,
"hits": [
{
"_index": "forum",
"_type": "article",
"_id": "2",
"_score": 1.344432,
"_source": {
"articleID": "KDKE-B-9947-#kL5",
"userID": 1,
"hidden": false,
"postDate": "2017-01-02",
"tag": [
"java"
],
"tag_cnt": 1,
"view_cnt": 50,
"title": "this is java blog",
"content": "i think java is the best programming language"
}
},
{
"_index": "forum",
"_type": "article",
"_id": "4",
"_score": 1.1365302,
"_source": {
"articleID": "QQPX-R-3956-#aD8",
"userID": 2,
"hidden": true,
"postDate": "2017-01-02",
"tag": [
"java",
"elasticsearch"
],
"tag_cnt": 2,
"view_cnt": 80,
"title": "this is java, elasticsearch, hadoop blog",
"content": "elasticsearch and hadoop are all very good solution, i am a beginner"
}
},
{
"_index": "forum",
"_type": "article",
"_id": "3",
"_score": 1.0341108,
"_source": {
"articleID": "JODL-X-1937-#pV7",
"userID": 2,
"hidden": false,
"postDate": "2017-01-01",
"tag": [
"hadoop"
],
"tag_cnt": 1,
"view_cnt": 100,
"title": "this is elasticsearch blog",
"content": "i am only an elasticsearch beginner"
}
},
{
"_index": "forum",
"_type": "article",
"_id": "5",
"_score": 0.7116974,
"_source": {
"articleID": "DHJK-B-1395-#Ky5",
"userID": 3,
"hidden": false,
"postDate": "2019-05-01",
"tag": [
"elasticsearch"
],
"tag_cnt": 1,
"view_cnt": 10,
"title": "this is spark blog",
"content": "spark is best big data solution based on scala ,an programming language similar to java"
}
},
{
"_index": "forum",
"_type": "article",
"_id": "1",
"_score": 0.4889865,
"_source": {
"articleID": "XHDK-A-1293-#fJ3",
"userID": 1,
"hidden": false,
"postDate": "2017-01-01",
"tag": [
"java",
"hadoop"
],
"tag_cnt": 2,
"view_cnt": 30,
"title": "this is java and elasticsearch blog",
"content": "i like to write best elasticsearch article"
}
}
]
}
}
