如何在MongoDB中更改字段名称？
> db.demo517.insertOne({"Name":"Chris Brown"});{
"acknowledged" : true,
"insertedId" : ObjectId("5e88a2a2987b6e0e9d18f595")
}
> db.demo517.insertOne({"Name":"David Miller"});{
"acknowledged" : true,
"insertedId" : ObjectId("5e88a2ab987b6e0e9d18f596")
}
> db.demo517.insertOne({"Name":"John Doe"});{
"acknowledged" : true,
"insertedId" : ObjectId("5e88a2b1987b6e0e9d18f597")
}在find()方法的帮助下显示集合中的所有文档-
> db.demo517.find();
这将产生以下输出-
{ "_id" : ObjectId("5e88a2a2987b6e0e9d18f595"), "Name" : "Chris Brown" }
{ "_id" : ObjectId("5e88a2ab987b6e0e9d18f596"), "Name" : "David Miller" }
{ "_id" : ObjectId("5e88a2b1987b6e0e9d18f597"), "Name" : "John Doe" }以下是更改字段名称的查询-
> db.demo517.aggregate([{$project:{FullName:"$Name"}}]);这将产生以下输出-
{ "_id" : ObjectId("5e88a2a2987b6e0e9d18f595"), "FullName" : "Chris Brown" }
{ "_id" : ObjectId("5e88a2ab987b6e0e9d18f596"), "FullName" : "David Miller" }
{ "_id" : ObjectId("5e88a2b1987b6e0e9d18f597"), "FullName" : "John Doe" }