MongoDB 聚合框架匹配或有可能吗?
我们先创建一个包含文档的集合。创建包含文档的集合的查询如下:
> db.aggregationFrameworkWithOrMatchDemo.insertOne({"StudentFirstName":"John", "StudentLastName":"Smith","StudentAge":23}); { "acknowledged" : true, "insertedId" : ObjectId("5c8ac3a96cea1f28b7aa080d") } > db.aggregationFrameworkWithOrMatchDemo.insertOne({"StudentFirstName":"Carol", "StudentLastName":"Tayor","StudentAge":24}); { "acknowledged" : true, "insertedId" : ObjectId("5c8ac3bc6cea1f28b7aa080e") } > db.aggregationFrameworkWithOrMatchDemo.insertOne({"StudentFirstName":"David", "StudentLastName":"Miller","StudentAge":21}); { "acknowledged" : true, "insertedId" : ObjectId("5c8ac3ce6cea1f28b7aa080f") } > db.aggregationFrameworkWithOrMatchDemo.insertOne({"StudentFirstName":"Bob", "StudentLastName":"Taylor","StudentAge":20}); { "acknowledged" : true, "insertedId" : ObjectId("5c8ac3e16cea1f28b7aa0810") } > db.aggregationFrameworkWithOrMatchDemo.insertOne({"StudentFirstName":"Robert", "StudentLastName":"Smith","StudentAge":20}); { "acknowledged" : true, "insertedId" : ObjectId("5c8ac3fb6cea1f28b7aa0811") } > db.aggregationFrameworkWithOrMatchDemo.insertOne({"StudentFirstName":"Mike", "StudentLastName":"Miller","StudentAge":27}); { "acknowledged" : true, "insertedId" : ObjectId("5c8ac4166cea1f28b7aa0812") }
使用 find() 方法显示集合中的所有文档。查询如下:
> db.aggregationFrameworkWithOrMatchDemo.find().pretty();
以下是输出:
{ "_id" : ObjectId("5c8ac3a96cea1f28b7aa080d"), "StudentFirstName" : "John", "StudentLastName" : "Smith", "StudentAge" : 23 } { "_id" : ObjectId("5c8ac3bc6cea1f28b7aa080e"), "StudentFirstName" : "Carol", "StudentLastName" : "Tayor", "StudentAge" : 24 } { "_id" : ObjectId("5c8ac3ce6cea1f28b7aa080f"), "StudentFirstName" : "David", "StudentLastName" : "Miller", "StudentAge" : 21 } { "_id" : ObjectId("5c8ac3e16cea1f28b7aa0810"), "StudentFirstName" : "Bob", "StudentLastName" : "Taylor", "StudentAge" : 20 } { "_id" : ObjectId("5c8ac3fb6cea1f28b7aa0811"), "StudentFirstName" : "Robert", "StudentLastName" : "Smith", "StudentAge" : 20 } { "_id" : ObjectId("5c8ac4166cea1f28b7aa0812"), "StudentFirstName" : "Mike", "StudentLastName" : "Miller", "StudentAge" : 27 }
以下是聚合框架匹配 OR 的查询。我们将考虑 StudentLastName 为 Smith 或 Miller:
> db.aggregationFrameworkWithOrMatchDemo.aggregate({ ... $match: { $or: [{ StudentLastName: 'Smith' }, { StudentLastName: 'Miller' }] }}).pretty();
以下是输出:
{ "_id" : ObjectId("5c8ac3a96cea1f28b7aa080d"), "StudentFirstName" : "John", "StudentLastName" : "Smith", "StudentAge" : 23 } { "_id" : ObjectId("5c8ac3ce6cea1f28b7aa080f"), "StudentFirstName" : "David", "StudentLastName" : "Miller", "StudentAge" : 21 } { "_id" : ObjectId("5c8ac3fb6cea1f28b7aa0811"), "StudentFirstName" : "Robert", "StudentLastName" : "Smith", "StudentAge" : 20 } { "_id" : ObjectId("5c8ac4166cea1f28b7aa0812"), "StudentFirstName" : "Mike", "StudentLastName" : "Miller", "StudentAge" : 27 }
广告