什麽是elasticsearch

elasticsearch是java基礎apache lucene的開源搜索引擎，開箱即用，elasticsearch有很多默認的合理的配置

elasticsearch作用

全文檢索，分布式實時文件存儲,分布式實時分析引擎,可以擴展到上百臺服務器處理PB級結構化數據或非結構化數據

elasticsearch安裝

官網下載:https://www.elastic.co/downloads/elasticsearch解壓

linux運行:./bin/elasticsearch

訪問:http://localhost:9200/?pretty

表示安裝成功

ES與傳統數據的區別

關系型數據庫:databases->tables->rows->columns

ES:indices->types->documents->Fileds

index可以理解成數據庫 type可以理解為表 doument可以理解為行 filed可以理解為列

索引名詞=數據庫 索引動詞可以理解為數據庫的insert語句 索引文檔如果存在 舊的將覆蓋新的 ES為字段建立的索引為倒排索引

建立索引

現在我們建立1個產品的索引(insert)

posman put請求

http://127.0.0.1:9200/opcmdev/product/1

body:

{
    "productName": "法瑞思 天然椰棕床墊棕墊硬床墊定做 薄乳膠棕櫚榻榻米床墊定制折疊1.2/1.5/1.8",
    "price": "10",
    "remark": "不錯的床墊",
    "tags": ["家具", "床墊", "棉花

我們可以理解為在opcmdev數據庫 product表 插入了一條產品信息 方便後面測試 多添加幾條數據

http://127.0.0.1:9200/opcmdev/product/2

{
    "productName": "南極人（Nanjiren）床墊家紡 加厚立體床墊羽絲絨床墊床褥子學生宿舍",
    
 
"price": "109",
    "remark": "不錯的床墊",
    "tags": ["家具", "床墊", "棉花被"]
}

http://127.0.0.1:9200/opcmdev/product/3

{
    "productName": "￥99.00誌高（CHIGO）電火鍋家用多功能電炒鍋電煮鍋不粘多用途鍋電熱鍋 ZG-RH2",
    "price": "99",
    "remark": "平底鍋",
    "tags": ["電器", "平底鍋"]
}

檢索文檔(查詢)

根據id查詢

get請求:http://127.0.0.1:9200/opcmdev/product/3

不帶條件的簡單搜索

get請求:http://127.0.0.1:9200/opcmdev/product/_search 默認返回前10條

{
    "took": 1,
    "timed_out": false,
    "_shards": {
        "total": 5,
        "successful": 5,
        "skipped": 0,
        "failed": 0
    },
    "hits": {
        "total": 3,
        "max_score": 1,
        "hits": [
            {
                "_index": "opcmdev",
                "_type": "product",
                "_id": "2",
                "_score": 1,
                "_source": {
                    "productName": "南極人（Nanjiren）床墊家紡 加厚立體床墊羽絲絨床墊床褥子學生宿舍",
                    "price": "109",
                    "remark": "不錯的床墊",
                    "tags": [
                        "家具",
                        "床墊",
                        "棉花被"
                    ]
                }
            },
            {
                "_index": "opcmdev",
                "_type": "product",
                "_id": "1",
                "_score": 1,
                "_source": {
                    "productName": "法瑞思 天然椰棕床墊棕墊硬床墊定做 薄乳膠棕櫚榻榻米床墊定制折疊1.2/1.5/1.8",
                    "price": "10",
                    "remark": "不錯的床墊",
                    "tags": [
                        "家具",
                        "床墊",
                        "棉花被"
                    ]
                }
            },
            {
                "_index": "opcmdev",
                "_type": "product",
                "_id": "3",
                "_score": 1,
                "_source": {
                    "productName": "￥99.00誌高（CHIGO）電火鍋家用多功能電炒鍋電煮鍋不粘多用途鍋電熱鍋 ZG-RH2",
                    "price": "99",
                    "remark": "平底鍋",
                    "tags": [
                        "電器",
                        "平底鍋"
                    ]
                }
            }
        ]
    }
}

http://127.0.0.1:9200/opcmdev/product/_search?q=productName:鍋

elasticsearch 權威指南入門閱讀筆記(一)