1、構造運行環境
打開kibana進入Dev tools,創建索引,並插入測試數據,代碼如下:
PUT /logs/_doc/1 { "Name":"燕麥", "Desc":"燕麥商品描述", "Price":111, "Tags":["Breakfast","Carbon","Cheap"] } PUT /logs/_doc/2 { "Name":"牛奶", "Desc":"牛奶商品描述", "Price":222, "Tags":["Breakfast","Nutrition","Expensive"] } PUT /logs/_doc/3 { "Name":"麪包", "Desc":"牛奶商品描述", "Price":333, "Tags":["Breakfast","Barley","Cheap","Carbon"] } PUT /logs/_doc/4 { "Name":"玉米", "Desc":"玉米商品描述", "Price":444, "Tags":["Breakfast","Vegetables","Cheap","Carbon"] } PUT /logs/_doc/5 { "Name":"葡萄", "Desc":"葡萄商品描述", "Price":555, "Tags":["Breakfast","Fruits","Expensive","Carbon"] }
執行以上代碼,並執行搜索,查看數據是否插入,簡單搜索代碼如下:
GET /logs/_search
或者
GET /logs/_search
{
"query": {
"match_all": {}
}
}
注：這裏相當於select * from 表名 where 1=1,match_all相當於匹配所有.
查詢結果集如下:
{ "took": 2,//當前請求花費的時間 "timed_out": false,//當前請求是否超時
//當前請求的分片情況 "_shards": { "total": 1, "successful": 1, "skipped": 0, "failed": 0 }, "hits": { "total": { "value": 5,//當前請求查詢到5條結果 "relation": "eq" //當前查詢的關係是等於 }, "max_score": 1, //當前查詢的評分,最大是1.0 "hits": [ { "_index": "logs", "_id": "1", "_score": 1, "_source": { "Name": "燕麥", "Desc": "燕麥商品描述", "Price": 111, "Tags": [ "Breakfast", "Carbon", "Cheap" ] } }, { "_index": "logs", "_id": "2", "_score": 1, "_source": { "Name": "牛奶", "Desc": "牛奶商品描述", "Price": 222, "Tags": [ "Breakfast", "Nutrition", "Expensive" ] } }, { "_index": "logs", "_id": "3", "_score": 1, "_source": { "Name": "麪包", "Desc": "牛奶商品描述", "Price": 333, "Tags": [ "Breakfast", "Barley", "Cheap", "Carbon" ] } }, { "_index": "logs", "_id": "4", "_score": 1, "_source": { "Name": "玉米", "Desc": "玉米商品描述", "Price": 444, "Tags": [ "Breakfast", "Vegetables", "Cheap", "Carbon" ] } }, "_index": "logs", "_id": "5", "_score": 1, "_source": { "Name": "葡萄", "Desc": "葡萄商品描述", "Price": 555, "Tags": [ "Breakfast", "Fruits", "Expensive", "Carbon" ] } } ] } }
這裏插入成功了.
2、相關度評分
1中的demo查詢結果集中有一個max_score字段就是相關度評分,當使用查詢接口時沒有指定排序字段,那麼ES就會按照每條記錄的評分進行排序.相關度評分中涉及到兩種算法,會在後續的文章中進行介紹.
3、元數據
1中的demo查詢結果集有一個source字段就是元數據,其大致結構如下
"_source": { "Name": "燕麥", "Desc": "燕麥商品描述", "Price": 111, "Tags": [ "Breakfast", "Carbon", "Cheap" ] }
結果類似與關係型數據庫中的表字段和相關的值.
3.1、禁用元數據(source)
3.1.1 優缺點
優點:節省存儲開銷
缺點:不支持update、update_by_query、reindex_api、不支持高亮、不支持reindex,更改mapping分析器以及版本升級、通過索引時查看原文檔進行聚合查詢會失效、導致自動修復索引的功能實現.
注：如果單純爲了介紹存儲開銷,可以使用壓縮索引,比禁用source更好.
3.1.2 通過創建索引時指定mapping配置來控制source
缺點：通過創建索引時指定mapping配置,來強制限制souce的字段查詢的方式或者在mapping中禁用source,設置之後將無法修改.
(1)、完全禁用source
PUT /logs { "mappings": { "_source": { "enabled": false } } }
(2)、禁用source中的部分字段
PUT /logs { "mappings": { "_source": { "includes": [ "Name", "Tags" ], "excludes": [ "Price", "Desc" ] } } }
通過指定includes和excludes來展示和禁用source中的字段
注：不推薦使用mapping的方式來控制source！！！！！！！
3.1.3 通過在查詢條件來控制source
(1)、查詢時禁用mapping
GET /logs/_search { "_source":false, "query": { "match_all": {} } }
這時結果集中不會包含mapping等相關信息,只包含index、id、score等相關信息.
(2)、常規搜索
GET /logs/_search { "_source": ["Name","Tags"], "query": { "match_all": {} } }
通過在api中指定_source來控制查詢結果返回的字段,類似與關係型數據庫中的 select Name,Tags from logs;
(3)、通配符查找
刪除1demo中的索引,新建以下索引
PUT /logs/_doc/1 { "Name":"燕麥", "Desc":"燕麥商品描述", "Price":111, "Items":{ "Name":"子名稱", "Price":222 }, "Tags":["Breakfast","Carbon","Cheap"] }
logs索引中包含一個Items的對象屬性,如果此時搜索只希望查Items的相關信息,可以執行以下操作
GET /logs/_search { "_source":["Items.*"], "query": { "match_all": {} } }
返回的結果如下:
"hits": [ { "_index": "logs", "_id": "1", "_score": 1, "_source": { "Items": { "Price": 222, "Name": "子名稱" } } } ]
(4)、includes查看和exincludes查找
GET /logs/_search { "_source":{ "includes": ["Items.*","Price","Desc"], "excludes": ["Name"] }, "query": { "match_all": {} } }
這裏可以指定查詢包含哪些字段和不包含哪些字段
4、QueryString 查詢
4.1 查詢所有
GET /logs/_search
4.2 分頁搜索
GET /logs/_search?from=0&size=3&sort=Price:desc
查詢從第from條開始,一共查size條數據,排序條件時Price按desc排序.
4.3 精準匹配
GET /logs/_search?q=Name:牛奶
這裏查詢的就是log中Name索引集合中值爲牛奶的document.
注:ES默認會爲所有的字段創建倒排索引,如果通過q=字段:字段值的形式進行搜索,ES會去指定字段的索引集合查找相關的值並返回.
4.4 all搜索
GET /logs/_search?q=111
重點注意:ES默認會爲所有的字段創建倒排索引,所以如4.3中一樣,查詢條件沒有以q=字段:字段值的形式進行搜索,ES掃描所有建立了倒排索引的字段.所以這裏的結果集如下:
"hits": [ { "_index": "logs", "_id": "2", "_score": 1.3167865, "_source": { "Name": "牛奶", "Desc": "牛奶商品描述111", "Price": 222, "Tags": [ "Breakfast", "Nutrition", "Expensive" ] } }, { "_index": "logs", "_id": "1", "_score": 1, "_source": { "Name": "燕麥", "Desc": "燕麥商品描述", "Price": 111, "Tags": [ "Breakfast", "Carbon", "Cheap" ] } } ]
Price和Desc中包含111的記錄都被檢索出來了.
注：這裏需要注意精準匹配的問題.demo中Desc字段會被分詞,在進行匹配,但是Price並不會.！！！