如何在 MongoDB 中追加数据?
mongodbdatabasebig data analytics更新于 2026/2/13 2:07:17
要在 MongoDB 中追加数据，请使用 $concatArrays。让我们创建一个包含文档的集合 −
> db.demo435.insertOne({"FirstName":["Chris"],"LastName":["Brown"]} );
{
"acknowledged" : true,
"insertedId" : ObjectId("5e7719b1bbc41e36cc3cae97")
}
> db.demo435.insertOne({"FirstName":["David"],"LastName":["Miller"]} );
{
"acknowledged" : true,
"insertedId" : ObjectId("5e7719bdbbc41e36cc3cae98")
}
> db.demo435.insertOne({"FirstName":["John"],"LastName":["Doe"]} );
{
"acknowledged" : true,
"insertedId" : ObjectId("5e7719c6bbc41e36cc3cae99")
}
借助 find() 方法显示集合中的所有文档 −
> db.demo435.find().pretty();
这将产生以下输出 −
{
"_id" : ObjectId("5e7719b1bbc41e36cc3cae97"),
"FirstName" : [
"Chris"
],
"LastName" : [
"Brown"
]
}
{
"_id" : ObjectId("5e7719bdbbc41e36cc3cae98"),
"FirstName" : [
"David"
],
"LastName" : [
"Miller"
]
}
{
"_id" : ObjectId("5e7719c6bbc41e36cc3cae99"),
"FirstName" : [
"John"
],
"LastName" : [
"Doe"
]
}
以下是附加到 MongoDB 数组的查询 −
> db.demo435.aggregate([ { $project: { FullName: { $concatArrays: [ "$FirstName", "$LastName" ] } } } ])
这将产生以下输出 −
{ "_id" : ObjectId("5e7719b1bbc41e36cc3cae97"), "FullName" : [ "Chris", "Brown" ] }
{ "_id" : ObjectId("5e7719bdbbc41e36cc3cae98"), "FullName" : [ "David", "Miller" ] }
{ "_id" : ObjectId("5e7719c6bbc41e36cc3cae99"), "FullName" : [ "John", "Doe" ] }
