MongoDB模糊查詢操作案例詳解(類關系型數據庫的 like 和 not like)

2020-10-29 18:41:33

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1.作用與語法描述

作用：正則表達式是使用指定字符串來描述、匹配一系列符合某個句法規則的字符串。許多程序設計語言都支持利用正則表達式進行字符串操作。MongoDB 使用 $regex 操作符來設置匹配字符串的正則表達式。

語法一

{ <field>: { $regex: /pattern/, $options: '<options>' } }{ <field>: { $regex: 'pattern', $options: '<options>' } }{ <field>: { $regex: /pattern/<options> } }

語法二

{ <field>: /pattern/<options> }

2.案例演示

假設MongoDB中存放了我們OrderService服務的消息信息，其數據如下：

（以下為演示所用到的9個文檔）

{  "_id" : ObjectId("5d305b1c4857fc49c0c14c81"),  "order" : "QQ00001",  "data" : "/"<?xml version='1.0' encoding='UTF-8'?><Response service=///"OrderService///"><Head>ERR</Head><ERROR>重復下單</ERROR></Response>/""},{  "_id" : ObjectId("5d305b3b4857fc49c0c14c82"),  "order" : "QQ00001",  "data" : "/"<?xml version='1.0' encoding='UTF-8'?><Response service=///"OrderService///"><Head>ERR</Head><ERROR>重復下單</ERROR></Response>/""},{  "_id" : ObjectId("5d305b404857fc49c0c14c83"),  "order" : "QQ00002",  "data" : "/"<?xml version='1.0' encoding='UTF-8'?><Response service=///"OrderService///"><Head>ERR</Head><ERROR>重復下單</ERROR></Response>/""},{  "_id" : ObjectId("5d305b454857fc49c0c14c84"),  "order" : "QQ00002",  "data" : "/"<?xml version='1.0' encoding='UTF-8'?><Response service=///"OrderService///"><Head>ERR</Head><ERROR>重復下單</ERROR></Response>/""},{  "_id" : ObjectId("5d305b4b4857fc49c0c14c85"),  "order" : "QQ00003",  "data" : "/"<?xml version='1.0' encoding='UTF-8'?><Response service=///"OrderService///"><Head>ERR</Head><ERROR>重復下單</ERROR></Response>/""},{  "_id" : ObjectId("5d305b4f4857fc49c0c14c86"),  "order" : "QQ00003",  "data" : "/"<?xml version='1.0' encoding='UTF-8'?><Response service=///"OrderService///"><Head>ERR</Head><ERROR>重復下單</ERROR></Response>/""},{  "_id" : ObjectId("5d305bb74857fc49c0c14c87"),  "order" : "QQ00003",  "data" : "/"<?xml version='1.0' encoding='UTF-8'?><Response service=///"OrderService///"><Head>OK</Head><Body><OrderResponse filter_mmm=///"2///" destcity=///"shenzheng///" origincode=///"QQ0003///" /></Body></Response>/""},{  "_id" : ObjectId("5d305bd14857fc49c0c14c88"),  "order" : "QQ00002",  "data" : "/"<?xml version='1.0' encoding='UTF-8'?><Response service=///"OrderService///"><Head>OK</Head><Body><OrderResponse filter_mmm=///"2///" destcity=///"zhongshan///" origincode=///"QQ0002///" /></Body></Response>/""},{  "_id" : ObjectId("5d305be94857fc49c0c14c89"),  "order" : "QQ00001",  "data" : "/"<?xml version='1.0' encoding='UTF-8'?><Response service=///"OrderService///"><Head>OK</Head><Body><OrderResponse filter_mmm=///"2///" destcity=///"zhongshan///" origincode=///"QQ0001///" /></Body></Response>/""}

需求：查詢 data 字段含有字符 <Head>OK</Head>的文檔

執行代碼如下：

db.dbtestregex.find({data:{ $regex:/<Head>OK<//Head>/}})

查詢代碼中的 / 為轉移符，以下查詢語句也是如此。

返回結果如下：

{  "_id" : ObjectId("5d305bb74857fc49c0c14c87"),  "order" : "QQ00003",  "data" : "/"<?xml version='1.0' encoding='UTF-8'?><Response service=///"OrderService///"><Head>OK</Head><Body><OrderResponse filter_mmm=///"2///" destcity=///"shenzheng///" origincode=///"QQ0003///" /></Body></Response>/""},{  "_id" : ObjectId("5d305bd14857fc49c0c14c88"),  "order" : "QQ00002",  "data" : "/"<?xml version='1.0' encoding='UTF-8'?><Response service=///"OrderService///"><Head>OK</Head><Body><OrderResponse filter_mmm=///"2///" destcity=///"zhongshan///" origincode=///"QQ0002///" /></Body></Response>/""},{  "_id" : ObjectId("5d305be94857fc49c0c14c89"),  "order" : "QQ00001",  "data" : "/"<?xml version='1.0' encoding='UTF-8'?><Response service=///"OrderService///"><Head>OK</Head><Body><OrderResponse filter_mmm=///"2///" destcity=///"zhongshan///" origincode=///"QQ0001///" /></Body></Response>/""}

上面的查詢命令也可以改寫成：

db.dbtestregex.find({data:/<Head>OK<//Head>/})

其查詢結果是一樣的，如下：

{  "_id" : ObjectId("5d305bb74857fc49c0c14c87"),  "order" : "QQ00003",  "data" : "/"<?xml version='1.0' encoding='UTF-8'?><Response service=///"OrderService///"><Head>OK</Head><Body><OrderResponse filter_mmm=///"2///" destcity=///"shenzheng///" origincode=///"QQ0003///" /></Body></Response>/""},{  "_id" : ObjectId("5d305bd14857fc49c0c14c88"),  "order" : "QQ00002",  "data" : "/"<?xml version='1.0' encoding='UTF-8'?><Response service=///"OrderService///"><Head>OK</Head><Body><OrderResponse filter_mmm=///"2///" destcity=///"zhongshan///" origincode=///"QQ0002///" /></Body></Response>/""},{  "_id" : ObjectId("5d305be94857fc49c0c14c89"),  "order" : "QQ00001",  "data" : "/"<?xml version='1.0' encoding='UTF-8'?><Response service=///"OrderService///"><Head>OK</Head><Body><OrderResponse filter_mmm=///"2///" destcity=///"zhongshan///" origincode=///"QQ0001///" /></Body></Response>/""}

還可以寫成：

db.dbtestregex.find({data:{ $regex:'<Head>OK<//Head>'}})

其實現功能一樣。

3.類關系型數據庫中的 not like 功能實現

反向查詢雖然不常見，但也是我們DBA必須的。下面我們做一個案例演示，看看在MongoDB中，怎么實現not like 功能的查詢。

需求查詢data 字段中不含 <Head>OK</Head>的文檔

執行腳本如下：

 db.dbtestregex.find({data:{ $not: /<Head>OK<//Head>/ }})

返回的文檔如下;

{  "_id" : ObjectId("5d305b1c4857fc49c0c14c81"),  "order" : "QQ00001",  "data" : "/"<?xml version='1.0' encoding='UTF-8'?><Response service=///"OrderService///"><Head>ERR</Head><ERROR>重復下單</ERROR></Response>/""},{  "_id" : ObjectId("5d305b3b4857fc49c0c14c82"),  "order" : "QQ00001",  "data" : "/"<?xml version='1.0' encoding='UTF-8'?><Response service=///"OrderService///"><Head>ERR</Head><ERROR>重復下單</ERROR></Response>/""},{  "_id" : ObjectId("5d305b404857fc49c0c14c83"),  "order" : "QQ00002",  "data" : "/"<?xml version='1.0' encoding='UTF-8'?><Response service=///"OrderService///"><Head>ERR</Head><ERROR>重復下單</ERROR></Response>/""},{  "_id" : ObjectId("5d305b454857fc49c0c14c84"),  "order" : "QQ00002",  "data" : "/"<?xml version='1.0' encoding='UTF-8'?><Response service=///"OrderService///"><Head>ERR</Head><ERROR>重復下單</ERROR></Response>/""},{  "_id" : ObjectId("5d305b4b4857fc49c0c14c85"),  "order" : "QQ00003",  "data" : "/"<?xml version='1.0' encoding='UTF-8'?><Response service=///"OrderService///"><Head>ERR</Head><ERROR>重復下單</ERROR></Response>/""},{  "_id" : ObjectId("5d305b4f4857fc49c0c14c86"),  "order" : "QQ00003",  "data" : "/"<?xml version='1.0' encoding='UTF-8'?><Response service=///"OrderService///"><Head>ERR</Head><ERROR>重復下單</ERROR></Response>/""}

更多內容可參照官方文檔 https://docs.mongodb.com/manual/reference/operator/query/regex/#op._S_regex

總結

以上所述是小編給大家介紹的MongoDB模糊查詢操作案例詳解(類關系型數據庫的 like 和 not like),希望對大家有所幫助，如果大家有任何疑問請給我留言，小編會及時回復大家的。在此也非常感謝大家對武林網網站的支持！
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