我们可以让score不走默认的，让他与我们某个field进行计算（加减乘除自己定义）得到一个结果作为score值
数据准备
follower_num：帖子阅读量
POST /forum/article/_bulk
{ "update": { "_id": "1"} }
{ "doc" : {"follower_num" : 5} }
{ "update": { "_id": "2"} }
{ "doc" : {"follower_num" : 10} }
{ "update": { "_id": "3"} }
{ "doc" : {"follower_num" : 25} }
{ "update": { "_id": "4"} }
{ "doc" : {"follower_num" : 3} }
{ "update": { "_id": "5"} }
{ "doc" : {"follower_num" : 60} }
将对帖子搜索得到的分数，跟follower_num进行运算，由follower_num在一定程度上增强帖子的分数
看帖子的人越多，那么帖子的分数就越高
GET /forum/article/_search
{
"query": {
"function_score": {
"query": {
"multi_match": {
"query": "java spark",
"fields": ["title", "content"]
}
},
"field_value_factor": {
"field": "follower_num"
}
}
}
}
结果：
{
"took": 124,
"timed_out": false,
"_shards": {
"total": 5,
"successful": 5,
"failed": 0
},
"hits": {
"total": 4,
"max_score": 40.994698,
"hits": [
{
"_index": "forum",
"_type": "article",
"_id": "5",
"_score": 40.994698,
"_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",
"follower_num": 60
}
},
{
"_index": "forum",
"_type": "article",
"_id": "2",
"_score": 6.8640785,
"_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",
"follower_num": 10
}
},
{
"_index": "forum",
"_type": "article",
"_id": "1",
"_score": 1.3371139,
"_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",
"follower_num": 5
}
},
{
"_index": "forum",
"_type": "article",
"_id": "4",
"_score": 0.46640402,
"_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",
"follower_num": 3
}
}
]
}
}
可以发现分数都特别的大，都在好几十。是因为它与我们的follower_num进行了乘法运算。
我们想让分数不要相差的这么离谱怎么办？ modifier
GET /forum/article/_search
{
"query": {
"function_score": {
"query": {
"multi_match": {
"query": "java spark",
"fields": ["title", "content"]
}
},
"field_value_factor": {
"field": "follower_num",
"modifier": "log1p"
}
}
}
}
结果
{
"took": 5,
"timed_out": false,
"_shards": {
"total": 5,
"successful": 5,
"failed": 0
},
"hits": {
"total": 4,
"max_score": 1.0189654,
"hits": [
{
"_index": "forum",
"_type": "article",
"_id": "5",
"_score": 1.0189654,
"_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",
"follower_num": 60
}
},
{
"_index": "forum",
"_type": "article",
"_id": "2",
"_score": 0.53412914,
"_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",
"follower_num": 10
}
},
{
"_index": "forum",
"_type": "article",
"_id": "1",
"_score": 0.14549617,
"_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",
"follower_num": 5
}
},
{
"_index": "forum",
"_type": "article",
"_id": "4",
"_score": 0.06186694,
"_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",
"follower_num": 3
}
}
]
}
}
公式会变为，new_score = old_score * log(1 + number_of_votes)，这样出来的分数会比较合理
再加个factor，可以进一步影响分数，new_score = old_score * log(1 + factor * number_of_votes)
GET /forum/article/_search
{
"query": {
"function_score": {
"query": {
"multi_match": {
"query": "java spark",
"fields": ["title", "content"]
}
},
"field_value_factor": {
"field": "follower_num",
"modifier": "log1p",
"factor": 0.5
}
}
}
}
结果
{
"took": 10,
"timed_out": false,
"_shards": {
"total": 5,
"successful": 5,
"failed": 0
},
"hits": {
"total": 4,
"max_score": 1.0189654,
"hits": [
{
"_index": "forum",
"_type": "article",
"_id": "5",
"_score": 1.0189654,
"_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",
"follower_num": 60
}
},
{
"_index": "forum",
"_type": "article",
"_id": "2",
"_score": 0.53412914,
"_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",
"follower_num": 10
}
},
{
"_index": "forum",
"_type": "article",
"_id": "1",
"_score": 0.14549617,
"_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",
"follower_num": 5
}
},
{
"_index": "forum",
"_type": "article",
"_id": "4",
"_score": 0.06186694,
"_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",
"follower_num": 3
}
}
]
}
}
我们不想乘法，想加上follower_num
GET /forum/article/_search
{
"query": {
"function_score": {
"query": {
"multi_match": {
"query": "java spark",
"fields": ["title", "content"]
}
},
"field_value_factor": {
"field": "follower_num",
"modifier": "log1p",
"factor": 0.5
},
"boost_mode": "sum"
}
}
}
结果
{
"took": 3,
"timed_out": false,
"_shards": {
"total": 5,
"successful": 5,
"failed": 0
},
"hits": {
"total": 4,
"max_score": 2.1746066,
"hits": [
{
"_index": "forum",
"_type": "article",
"_id": "5",
"_score": 2.1746066,
"_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",
"follower_num": 60
}
},
{
"_index": "forum",
"_type": "article",
"_id": "2",
"_score": 1.4645591,
"_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",
"follower_num": 10
}
},
{
"_index": "forum",
"_type": "article",
"_id": "1",
"_score": 0.81149083,
"_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",
"follower_num": 5
}
},
{
"_index": "forum",
"_type": "article",
"_id": "4",
"_score": 0.553408,
"_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",
"follower_num": 3
}
}
]
}
}
boost_mode，可以决定分数与指定字段的值如何计算，multiply，sum，min，max，replace
max_boost，限制计算出来的分数不要超过max_boost指定的值
GET /forum/article/_search
{
"query": {
"function_score": {
"query": {
"multi_match": {
"query": "java spark",
"fields": ["title", "content"]
}
},
"field_value_factor": {
"field": "follower_num",
"modifier": "log1p",
"factor": 0.5
},
"boost_mode": "sum",
"max_boost": 2
}
}
}
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