Elasticsearch高手进阶篇(27)
深度探秘搜索技术_深入揭秘lucene的相关度分数算法
整个es的相关度评分的
-
算法思想
- TF/IDF
- vector model
- boolean model
-
实际的公式
- query norm
- query coordination
- boost
对相关度评分进行调节和优化的常见的4种方法
- query-time boost
- 添加boost，针对于不同的query的请求的权重
GET /waws/article/_search
{
"query": {
"bool": {
"should": [
{
"match": {
"title": {
"query": "java spark",
"boost": 2
}
}
},
{
"match": {
"content": "java spark"
}
}
]
}
}
}
{
"took": 14,
"timed_out": false,
"_shards": {
"total": 5,
"successful": 5,
"failed": 0
},
"hits": {
"total": 4,
"max_score": 1.258609,
"hits": [
{
"_index": "waws",
"_type": "article",
"_id": "5",
"_score": 1.258609,
"_source": {
"articleID": "DHJK-B-1395-#Ky5",
"userID": 3,
"hidden": false,
"postDate": "2017-03-01",
"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 spark",
"sub_title": "haha, hello world",
"author_first_name": "Tonny",
"author_last_name": "Peter Smith",
"new_author_last_name": "Peter Smith",
"new_author_first_name": "Tonny"
}
},
{
"_index": "waws",
"_type": "article",
"_id": "2",
"_score": 1.083544,
"_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",
"sub_title": "learned a lot of course",
"author_first_name": "Smith",
"author_last_name": "Williams",
"new_author_last_name": "Williams",
"new_author_first_name": "Smith"
}
},
{
"_index": "waws",
"_type": "article",
"_id": "1",
"_score": 0.53484553,
"_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",
"sub_title": "learning more courses",
"author_first_name": "Peter",
"author_last_name": "Smith",
"new_author_last_name": "Smith",
"new_author_first_name": "Peter"
}
},
{
"_index": "waws",
"_type": "article",
"_id": "4",
"_score": 0.310936,
"_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",
"sub_title": "both of them are good",
"author_first_name": "Robbin",
"author_last_name": "Li",
"new_author_last_name": "Li",
"new_author_first_name": "Robbin"
}
}
]
}
}
- 重构查询结构
- 重构查询结果，在es新版本中，影响越来越小了。一般情况下，没什么必要的话，大家不用也行
- 影响到的是不同层次中query的权重
GET /waws/article/_search
{
"query": {
"bool": {
"should": [
{
"match": {
"content": "java"
}
},
{
"match": {
"content": "spark"
}
},
{
"bool": {
"should": [
{
"match": {
"content": "solution"
}
},
{
"match": {
"content": "beginner"
}
}
]
}
}
]
}
}
}
{
"took": 2,
"timed_out": false,
"_shards": {
"total": 5,
"successful": 5,
"failed": 0
},
"hits": {
"total": 4,
"max_score": 1.113083,
"hits": [
{
"_index": "waws",
"_type": "article",
"_id": "4",
"_score": 1.113083,
"_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",
"sub_title": "both of them are good",
"author_first_name": "Robbin",
"author_last_name": "Li",
"new_author_last_name": "Li",
"new_author_first_name": "Robbin"
}
},
{
"_index": "waws",
"_type": "article",
"_id": "5",
"_score": 0.970927,
"_source": {
"articleID": "DHJK-B-1395-#Ky5",
"userID": 3,
"hidden": false,
"postDate": "2017-03-01",
"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 spark",
"sub_title": "haha, hello world",
"author_first_name": "Tonny",
"author_last_name": "Peter Smith",
"new_author_last_name": "Peter Smith",
"new_author_first_name": "Tonny"
}
},
{
"_index": "waws",
"_type": "article",
"_id": "2",
"_score": 0.68640786,
"_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",
"sub_title": "learned a lot of course",
"author_first_name": "Smith",
"author_last_name": "Williams",
"new_author_last_name": "Williams",
"new_author_first_name": "Smith"
}
},
{
"_index": "waws",
"_type": "article",
"_id": "3",
"_score": 0.26742277,
"_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",
"sub_title": "we have a lot of fun",
"author_first_name": "Jack",
"author_last_name": "Ma",
"new_author_last_name": "Ma",
"new_author_first_name": "Jack"
}
}
]
}
}
- negative boost
- 搜索包含java，不包含spark的doc，但是这样子很死板
- 搜索包含java，尽量不包含spark的doc，如果包含了spark，不会说排除掉这个doc，而是说将这个doc的分数降低
- 包含了negative term的doc，分数乘以negative boost，分数降低
GET /forum/article/_search
{
"query": {
"bool": {
"must": [
{
"match": {
"content": "java"
}
}
],
"must_not": [
{
"match": {
"content": "spark"
}
}
]
}
}
}
{
"took": 50,
"timed_out": false,
"_shards": {
"total": 5,
"successful": 5,
"failed": 0
},
"hits": {
"total": 1,
"max_score": 0.68640786,
"hits": [
{
"_index": "waws",
"_type": "article",
"_id": "2",
"_score": 0.68640786,
"_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",
"sub_title": "learned a lot of course",
"author_first_name": "Smith",
"author_last_name": "Williams",
"new_author_last_name": "Williams",
"new_author_first_name": "Smith"
}
}
]
}
}
GET /waws/article/_search
{
"query": {
"boosting": {
"positive": {
"match": {
"content": "java"
}
},
"negative": {
"match": {
"content": "spark"
}
},
"negative_boost": 0.2
}
}
}
{
"took": 53,
"timed_out": false,
"_shards": {
"total": 5,
"successful": 5,
"failed": 0
},
"hits": {
"total": 2,
"max_score": 0.68640786,
"hits": [
{
"_index": "waws",
"_type": "article",
"_id": "2",
"_score": 0.68640786,
"_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",
"sub_title": "learned a lot of course",
"author_first_name": "Smith",
"author_last_name": "Williams",
"new_author_last_name": "Williams",
"new_author_first_name": "Smith"
}
},
{
"_index": "waws",
"_type": "article",
"_id": "5",
"_score": 0.05753642,
"_source": {
"articleID": "DHJK-B-1395-#Ky5",
"userID": 3,
"hidden": false,
"postDate": "2017-03-01",
"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 spark",
"sub_title": "haha, hello world",
"author_first_name": "Tonny",
"author_last_name": "Peter Smith",
"new_author_last_name": "Peter Smith",
"new_author_first_name": "Tonny"
}
}
]
}
}
negative的doc，会乘以negative_boost，降低分数
- constant_score
- 如果你压根儿不需要相关度评分，直接走constant_score加filter，所有的doc分数都是1，没有评分的概念了
GET /waws/article/_search
{
"query": {
"bool": {
"should": [
{
"constant_score": {
"query": {
"match": {
"title": "java"
}
}
}
},
{
"constant_score": {
"query": {
"match": {
"title": "spark"
}
}
}
}
]
}
}
}
{
"took": 1,
"timed_out": false,
"_shards": {
"total": 5,
"successful": 5,
"failed": 0
},
"hits": {
"total": 4,
"max_score": 1,
"hits": [
{
"_index": "waws",
"_type": "article",
"_id": "5",
"_score": 1,
"_source": {
"articleID": "DHJK-B-1395-#Ky5",
"userID": 3,
"hidden": false,
"postDate": "2017-03-01",
"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 spark",
"sub_title": "haha, hello world",
"author_first_name": "Tonny",
"author_last_name": "Peter Smith",
"new_author_last_name": "Peter Smith",
"new_author_first_name": "Tonny"
}
},
{
"_index": "waws",
"_type": "article",
"_id": "2",
"_score": 1,
"_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",
"sub_title": "learned a lot of course",
"author_first_name": "Smith",
"author_last_name": "Williams",
"new_author_last_name": "Williams",
"new_author_first_name": "Smith"
}
},
{
"_index": "waws",
"_type": "article",
"_id": "4",
"_score": 1,
"_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",
"sub_title": "both of them are good",
"author_first_name": "Robbin",
"author_last_name": "Li",
"new_author_last_name": "Li",
"new_author_first_name": "Robbin"
}
},
{
"_index": "waws",
"_type": "article",
"_id": "1",
"_score": 1,
"_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",
"sub_title": "learning more courses",
"author_first_name": "Peter",
"author_last_name": "Smith",
"new_author_last_name": "Smith",
"new_author_first_name": "Peter"
}
}
]
}
}
