MongoDB模糊查询操作案例详解(类关系型数据库的 like 和 not like)

2020-10-29 18:41:33

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1.作用与语法描述

作用：正则表达式是使用指定字符串来描述、匹配一系列符合某个句法规则的字符串。许多程序设计语言都支持利用正则表达式进行字符串操作。MongoDB 使用 $regex 操作符来设置匹配字符串的正则表达式。

语法一

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

语法二

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

2.案例演示

假设MongoDB中存放了我们OrderService服务的消息信息，其数据如下：

（以下为演示所用到的9个文档）

{  "_id" : ObjectId("5d305b1c4857fc49c0c14c81"),  "order" : "QQ00001",  "data" : "/"<?xml version='1.0' encoding='UTF-8'?><Response service=///"OrderService///"><Head>ERR</Head><ERROR>重复下单</ERROR></Response>/""},{  "_id" : ObjectId("5d305b3b4857fc49c0c14c82"),  "order" : "QQ00001",  "data" : "/"<?xml version='1.0' encoding='UTF-8'?><Response service=///"OrderService///"><Head>ERR</Head><ERROR>重复下单</ERROR></Response>/""},{  "_id" : ObjectId("5d305b404857fc49c0c14c83"),  "order" : "QQ00002",  "data" : "/"<?xml version='1.0' encoding='UTF-8'?><Response service=///"OrderService///"><Head>ERR</Head><ERROR>重复下单</ERROR></Response>/""},{  "_id" : ObjectId("5d305b454857fc49c0c14c84"),  "order" : "QQ00002",  "data" : "/"<?xml version='1.0' encoding='UTF-8'?><Response service=///"OrderService///"><Head>ERR</Head><ERROR>重复下单</ERROR></Response>/""},{  "_id" : ObjectId("5d305b4b4857fc49c0c14c85"),  "order" : "QQ00003",  "data" : "/"<?xml version='1.0' encoding='UTF-8'?><Response service=///"OrderService///"><Head>ERR</Head><ERROR>重复下单</ERROR></Response>/""},{  "_id" : ObjectId("5d305b4f4857fc49c0c14c86"),  "order" : "QQ00003",  "data" : "/"<?xml version='1.0' encoding='UTF-8'?><Response service=///"OrderService///"><Head>ERR</Head><ERROR>重复下单</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：查询 data 字段含有字符 <Head>OK</Head>的文档

执行代码如下：

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

查询代码中的 / 为转移符，以下查询语句也是如此。

返回结果如下：

{  "_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>/""}

上面的查询命令也可以改写成：

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

其查询结果是一样的，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>/""}

还可以写成：

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

其实现功能一样。

3.类关系型数据库中的 not like 功能实现

反向查询虽然不常见，但也是我们DBA必须的。下面我们做一个案例演示，看看在MongoDB中，怎么实现not like 功能的查询。

需求查询data 字段中不含 <Head>OK</Head>的文档

执行脚本如下：

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

返回的文档如下;

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

更多内容可参照官方文档 https://docs.mongodb.com/manual/reference/operator/query/regex/#op._S_regex

总结

以上所述是小编给大家介绍的MongoDB模糊查询操作案例详解(类关系型数据库的 like 和 not like),希望对大家有所帮助，如果大家有任何疑问请给我留言，小编会及时回复大家的。在此也非常感谢大家对武林网网站的支持！
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