db.getCollection()（mongosh方法）

定义

db.getCollection(name)

Returns a collection or a view object that is functionally equivalent to using the db.<collectionName> syntax. The method is useful for a collection or a view whose name might interact with mongosh itself, such as names that begin with _ or that match a database shell method.

The db.getCollection() method has the following parameter:

Parameter	类型	说明
name	字符串	集合的名称。

兼容性

此方法可用于以下环境中托管的部署：

• MongoDB Atlas：用于云中 MongoDB 部署的完全托管服务

• MongoDB Enterprise：基于订阅、自我管理的 MongoDB 版本

• MongoDB Community：源代码可用、免费使用且可自行管理的 MongoDB 版本

行为

The db.getCollection() object can access any collection methods.

指定的集合可能存在于服务器上，也可能不存在。如果该集合不存在，则 MongoDB 会将其作为写入操作（如 db.collection.insertOne()）的一部分隐式创建。

例子

The following example uses db.getCollection() to access the auth collection and insert a document into it.

var authColl = db.getCollection("auth")
authColl.insertOne(
   {
       usrName : "John Doe",
       usrDept : "Sales",
       usrTitle : "Executive Account Manager",
       authLevel : 4,
       authDept : [ "Sales", "Customers"]
   }
)

此操作将返回：

{
   "acknowledged" : true,
   "insertedId" : ObjectId("569525e144fe66d60b772763")
}

The previous example requires the use of db.getCollection("auth") because of a name conflict with the database method db.auth(). Calling db.auth directly to perform an insert operation would reference the db.auth() method and would error.

The following example attempts the same operation, but without using the db.getCollection() method:

db.auth.insertOne(
   {
       usrName : "John Doe",
       usrDept : "Sales",
       usrTitle : "Executive Account Manager",
       authLevel : 4,
       authDept : [ "Sales", "Customers"]
   }
)

操作错误，因为 db.auth() 方法没有 insertOne 方法。