概念 NOSQL not only SQL 文档型数据库，按列存储，分布式架构，批量写入性能好

教程学习札记

db.getCollection("111").find({"name":"Jane"})

关联关系设计

Example1 引用关系

{"_id":ObjectId("52ffc33cd85242f436000001"),"contact": "987654321","dob": "01-01-1991","name": "Tom Benzamin","address_ids": [ObjectId("52ffc4a5d85242602e000000"),ObjectId("52ffc4a5d85242602e000001")]
}

{"_id" : ObjectId("52ffc4a5d85242602e000000"),"building" : "170 A, Acropolis Apt","pincode" : 456789,"city" : "Chicago","state" : "Illinois"
}{"_id" : ObjectId("52ffc4a5d85242602e000001"),"building" : "170 A, Acropolis Apt","pincode" : 456789,"city" : "Chicago","state" : "Illinois"
}

查询方法 

var result= db.user.findOne({"name":"Tom Benzamin"},{"address_ids":1})
db.address.find({"_id":{"$in":result["address_ids"]}})

Example 2 嵌入式引用

{"_id":ObjectId("52ffc33cd85242f436000001"),"contact": "987654321","dob": "01-01-1991","name": "Tom Benzamin","address": [{"building": "22 A, Indiana Apt","pincode": 123456,"city": "Los Angeles","state": "California"},{"building": "170 A, Acropolis Apt","pincode": 456789,"city": "Chicago","state": "Illinois"}]
} 

>db.users.findOne({"name":"Tom Benzamin"},{"address":1})