Elasticsearch搜尋引擎學習筆記（五）
阿新 • • 發佈：2021-06-23
搜尋功能
資料準備
1、自定義詞庫
慕課網
慕課
課網
慕
課
網
2、新建立索引shop
3、建立mappings
POST /shop/_mapping （7.x之前的版本：/shop/_mapping/_doc）
{
"properties": {
"id": {
"type": "long"
},
"age": {
"type": "integer"
},
"username": {
"type": "keyword"
},
"nickname": {
"type": "text",
"analyzer": "ik_max_word"
},
"money": {
"type": "float"
},
"desc": {
"type": "text",
"analyzer": "ik_max_word"
},
"sex": {
"type": "byte"
},
"birthday": {
"type": "date"
},
"face": {
"type": "text",
"index": false
}
}
}
4、錄入資料
POST /shop/_doc/1001
{
"id": 1001,
"age": 18,
"username": "imoocAmazing",
"nickname": "慕課網",
"money": 88.8,
"desc": "我在慕課網學習java和前端，學習到了很多知識",
"sex": 0,
"birthday": "1992-12-24",
"face": "https://www.imooc.com/static/img/index/logo.png"
}
{
"id": 1002,
"age": 19,
"username": "justbuy",
"nickname": "周杰棍",
"money": 77.8,
"desc": "今天上下班都很堵，車流量很大",
"sex": 1,
"birthday": "1993-01-24",
"face": "https://www.imooc.com/static/img/index/logo.png"
}
{
"id": 1003,
"age": 20,
"username": "bigFace",
"nickname": "飛翔的巨鷹",
"money": 66.8,
"desc": "慕課網團隊和導遊坐飛機去海外旅遊，去了新馬泰和歐洲",
"sex": 1,
"birthday": "1996-01-14",
"face": "https://www.imooc.com/static/img/index/logo.png"
}
{
"id": 1004,
"age": 22,
"username": "flyfish",
"nickname": "水中魚",
"money": 55.8,
"desc": "昨天在學校的池塘裡，看到有很多魚在游泳，然後就去慕課網上課了",
"sex": 0,
"birthday": "1988-02-14",
"face": "https://www.imooc.com/static/img/index/logo.png"
}
{
"id": 1005,
"age": 25,
"username": "gotoplay",
"nickname": "ps遊戲機",
"money": 155.8,
"desc": "今年生日，女友送了我一臺play station遊戲機，非常好玩，非常不錯",
"sex": 1,
"birthday": "1989-03-14",
"face": "https://www.imooc.com/static/img/index/logo.png"
}
{
"id": 1006,
"age": 19,
"username": "missimooc",
"nickname": "我叫小慕",
"money": 156.8,
"desc": "我叫凌雲慕，今年20歲，是一名律師，我在琦䯲星球做演講",
"sex": 1,
"birthday": "1993-04-14",
"face": "https://www.imooc.com/static/img/index/logo.png"
}
{
"id": 1007,
"age": 19,
"username": "msgame",
"nickname": "gamexbox",
"money": 1056.8,
"desc": "明天去進貨，最近微軟處理很多遊戲機，還要買xbox遊戲卡帶",
"sex": 1,
"birthday": "1985-05-14",
"face": "https://www.imooc.com/static/img/index/logo.png"
}
{
"id": 1008,
"age": 19,
"username": "muke",
"nickname": "慕學習",
"money": 1056.8,
"desc": "大學畢業後，可以到imooc.com進修",
"sex": 1,
"birthday": "1995-06-14",
"face": "https://www.imooc.com/static/img/index/logo.png"
}
{
"id": 1009,
"age": 22,
"username": "shaonian",
"nickname": "騷年輪",
"money": 96.8,
"desc": "騷年在大學畢業後，考研究生去了",
"sex": 1,
"birthday": "1998-07-14",
"face": "https://www.imooc.com/static/img/index/logo.png"
}
{
"id": 1010,
"age": 30,
"username": "tata",
"nickname": "隔壁老王",
"money": 100.8,
"desc": "隔壁老外去國外出差，帶給我很多好吃的",
"sex": 1,
"birthday": "1988-07-14",
"face": "https://www.imooc.com/static/img/index/logo.png"
}
{
"id": 1011,
"age": 31,
"username": "sprder",
"nickname": "皮特帕克",
"money": 180.8,
"desc": "它是一個超級英雄",
"sex": 1,
"birthday": "1989-08-14",
"face": "https://www.imooc.com/static/img/index/logo.png"
}
{
"id": 1012,
"age": 31,
"username": "super hero",
"nickname": "super hero",
"money": 188.8,
"desc": "BatMan, GreenArrow, SpiderMan, IronMan... are all Super Hero",
"sex": 1,
"birthday": "1980-08-14",
"face": "https://www.imooc.com/static/img/index/logo.png"
}
請求引數的查詢(QueryString)
GET /shop/_doc/_search?q=desc:慕課網 GET /shop/_doc/_search?q=nickname:慕&q=age:25
DSL查詢
QueryString用的很少，一旦引數複雜就難以構建，所以大多查詢都會使用dsl來進行查詢更好。
# 查詢
POST /shop/_doc/_search
{
"query": {
"match": {
"desc": "慕課網"
}
}
}
# 判斷某個欄位是否存在
{
"query": {
"exists": {
"field": "desc"
}
}
}查詢所有
GET /shop/_doc/_search
或
POST /shop/_doc/_search
{
"query": {
"match_all": {}
},
"_source": ["id", "nickname", "age"]
}
分頁
POST /shop/_doc/_search
{
"query": {
"match_all": {}
},
"from": 0,
"size": 10
}
{
"query": {
"match_all": {}
},
"_source": [
"id",
"nickname",
"age"
],
"from": 0,
"size": 10
}
term精確搜尋與match分詞搜尋
term搜尋的時候會把使用者搜尋內容，比如“慕課網強大”作為一整個關鍵詞去搜索，而不會對其進行分詞後再搜尋；
match會把使用者搜尋內容分詞，然後再搜尋
POST /shop/_doc/_search
{
"query": {
"term": {
"desc": "慕課網"
}
}
}
對比
{
"query": {
"match": {
"desc": "慕課網"
}
}
}
terms 多個詞語匹配檢索
POST /shop/_doc/_search
{
"query": {
"terms": {
"desc": ["慕課網", "學習", "騷年"]
}
}
}
match_phrase 短語匹配
match：分詞後只要有匹配就返回，match_phrase：分詞結果必須在text欄位分詞中都包含，而且順序必須相同，而且必須都是連續的。（搜尋比較嚴格）
slop：允許詞語間跳過的數量，是“詞”的數量，不是“字”的數量
POST /shop/_doc/_search
{
"query": {
"match_phrase": {
"desc": {
"query": "大學 畢業 研究生",
"slop": 2
}
}
}
}
match（operator）
operator
or：搜尋內容分詞後，只要存在一個詞語匹配就展示結果
and：搜尋內容分詞後，都要滿足詞語匹配。
POST /shop/_doc/_search
{
"query": {
"match": {
"desc": "慕課網"
}
}
}
# 等同於
{
"query": {
"match": {
"desc": {
"query": "xbox遊戲機",
"operator": "or"
}
}
}
}
# 相當於 select * from shop where desc='xbox' or|and desc='遊戲機'
match（minimum_should_match）
minimum_should_match
minimum_should_match: 最低匹配精度，至少有[分詞後的詞語個數]x百分百，得出一個數據值取整。舉個例子：當前屬性設定為<code>70</code>，若一個使用者查詢檢索內容分詞後有10個詞語，那麼匹配度按照 10x70%=7，則desc中至少需要有7個詞語匹配，就展示；若分詞後有8個，則 8x70%=5.6，則desc中至少需要有5個詞語匹配，就展示。
minimum_should_match 也能設定具體的數字，表示個數
POST /shop/_doc/_search
{
"query": {
"match": {
"desc": {
"query": "女友生日送我好玩的xbox遊戲機",
"minimum_should_match": "60%"
}
}
}
}
根據文件主鍵ids搜尋
GET /shop/_doc/1001
或
POST /shop/_doc/_search
{
"query": {
"ids": {
"type": "_doc",
"values": ["1001", "1010", "1008"]
}
}
}