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1 制作案例

POST /forum/article/_bulk
{ "update": { "_id": "1"} }
{ "doc" : {"author_first_name" : "Peter", "author_last_name" : "Smith"} }
{ "update": { "_id": "2"} }
{ "doc" : {"author_first_name" : "Smith", "author_last_name" : "Williams"} }
{ "update": { "_id": "3"} }
{ "doc" : {"author_first_name" : "Jack", "author_last_name" : "Ma"} }
{ "update": { "_id": "4"} }
{ "doc" : {"author_first_name" : "Robbin", "author_last_name" : "Li"} }
{ "update": { "_id": "5"} }
{ "doc" : {"author_first_name" : "Tonny", "author_last_name" : "Peter Smith"} }//实现cross-fields搜索
PUT /forum/_mapping/article
{"properties": {"new_author_first_name": {"type":     "string","copy_to":  "new_author_full_name" },"new_author_last_name": {"type":     "string","copy_to":  "new_author_full_name" },"new_author_full_name": {"type":     "string"}}
}//其实效果不佳
POST /forum/article/_bulk
{ "update": { "_id": "1"} }
{ "doc" : {"new_author_first_name" : "Peter", "new_author_last_name" : "Smith"} }     --> Peter Smith
{ "update": { "_id": "2"} }
{ "doc" : {"new_author_first_name" : "Smith", "new_author_last_name" : "Williams"} }      --> Smith Williams
{ "update": { "_id": "3"} }
{ "doc" : {"new_author_first_name" : "Jack", "new_author_last_name" : "Ma"} }         --> Jack Ma
{ "update": { "_id": "4"} }
{ "doc" : {"new_author_first_name" : "Robbin", "new_author_last_name" : "Li"} }           --> Robbin Li
{ "update": { "_id": "5"} }
{ "doc" : {"new_author_first_name" : "Tonny", "new_author_last_name" : "Peter Smith"} }       --> Tonny Peter SmithGET /forum/article/_search
{"query": {"match": {"new_author_full_name":       "Peter Smith"}}
}//测试短语匹配
POST /forum/article/5/_update
{"doc": {"content": "spark is best big data solution based on scala ,an programming language similar to java spark"}
}//单单包含java的doc也返回了，不是我们想要的结果
GET /forum/article/_search
{"query": {"match": {"content": "java spark"}}
}
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2 短语匹配(match_phrase)

• 要求：只有包含java spark这个短语的doc才返回了，只包含java的doc不会返回

GET /forum/article/_search
{"query": {"match_phrase": {"content": "java spark"}}
}
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• term position的意思

hello world, java spark       doc1
hi, spark java          doc2hello       doc1(0)
wolrd       doc1(1)
java        doc1(2) doc2(2)
spark       doc1(3) doc2(1)了解什么是分词后的positionGET _analyze
{"text": "hello world, java spark","analyzer": "standard"
}
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3 近似匹配(slop)

• query string，搜索文本中的几个term，要经过几次移动才能与一个document匹配，这个移动的次数，就是slop
• slop的含义，不仅仅是说一个query string terms移动几次，跟一个doc匹配上。一个query string terms，最多可以移动几次去尝试跟一个doc匹配上
• slop搜索下，关键词离的越近，relevance score就会越高，

GET /forum/article/_search
{"query": {"match_phrase": {"content": {"query": "spark data","slop": 3}}}
}spark is best big data solution based on scala ,an programming language similar to java sparkspark data--> data--> data
spark         --> dataGET /forum/article/_search
{"query": {"match_phrase": {"content": {"query": "java best","slop": 15}}}
}{"took": 3,"timed_out": false,"_shards": {"total": 5,"successful": 5,"failed": 0},"hits": {"total": 2,"max_score": 0.65380025,"hits": [{"_index": "forum","_type": "article","_id": "2","_score": 0.65380025,"_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": "forum","_type": "article","_id": "5","_score": 0.07111243,"_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"}}]}
}
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4 优先满足召回率

• 优先满足召回率，意思是：java spark，包含java的也返回，包含spark的也返回，包含java和spark的也返回；同时兼顾精准度，就是包含java和spark，同时java和spark离的越近的doc排在最前面

GET /forum/article/_search
{"query": {"bool": {"must": [{"match": {"content": "java spark"}}],"should": [{"match_phrase": {"content": {"query": "java spark","slop": 50}}}]}}
}{"took": 5,"timed_out": false,"_shards": {"total": 5,"successful": 5,"failed": 0},"hits": {"total": 2,"max_score": 1.258609,"hits": [{"_index": "forum","_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","followers": ["Jack","Robbin Li"]}},{"_index": "forum","_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","followers": ["Tom","Jack"]}}]}
}
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5 总结

执笔小记，温故知新

专注于大数据及容器云核心技术解密，可提供全栈的大数据+云原生平台咨询方案，请持续关注本套博客。如有任何学术交流，可随时联系。更多内容请关注《数据云技术社区》公众号。