mongosh Help帮助

Show Available Databases显示可用数据库

To see the list of databases available to you on the server, use the show dbs command:要查看服务器上可用的数据库列表，请使用show dbs命令：

show dbs

show databases is an alias for show dbs.是show dbs的别名。

Show Database Methods显示数据库方法

To see the list of database methods you can use on the db object, run db.help():要查看可以在db对象上使用的数据库方法列表，请运行db.help()：

db.help()

The output resembles the following abbreviated list:输出类似于以下缩写列表：

Database Class:

  getMongo                      Returns the current database connection
  getName                       Returns the name of the DB
  getCollectionNames            Returns an array containing the names of all collections in the current database.
  getCollectionInfos            Returns an array of documents with collection information, i.e. collection name and options, for the current database.
  runCommand                    Runs an arbitrary command on the database.
  adminCommand                  Runs an arbitrary command against the admin database.
  ...

Show Help for a Specific Database Method显示特定数据库方法的帮助

To see help for a specific database method in mongosh, type the db.<method name>, followed by .help or .help(). The following example returns help for the db.adminCommand() method:要查看mongosh中特定数据库方法的帮助，请键入db.<method name>，后跟.help或.help()。以下示例返回db.adminCommand()方法的帮助：

db.adminCommand.help()

The output resembles the following:输出类似于以下内容：

  db.adminCommand({ serverStatus: 1 }):

  Runs an arbitrary command against the admin database.

  For more information on usage: https://www.mongodb.com/docs/manual/reference/method/db.adminCommand

Show Additional Usage Details for a Database Method显示数据库方法的其他用法详细信息

To see additional usage details for a database method in mongosh, type the db.<method name> without the parenthesis (()). 要查看mongosh中数据库方法的其他使用细节，请键入db.<method name>不带小括号（()）。The following example returns details about the db.adminCommand() method:以下示例返回有关db.adminCommand()方法的详细信息：

db.adminCommand

The output resembles the following:输出类似于以下内容：

[Function: adminCommand] AsyncFunction {
  apiVersions: [ 1, Infinity ],
  serverVersions: [ '3.4.0', '999.999.999' ],
  returnsPromise: true,
  topologies: [ 'ReplSet', 'Sharded', 'LoadBalanced', 'Standalone' ],
  returnType: { type: 'unknown', attributes: {} },
  deprecated: false,
  platforms: [ 0, 1, 2 ],
  isDirectShellCommand: false,
  acceptsRawInput: false,
  shellCommandCompleter: undefined,
  help: [Function (anonymous)] Help
}

List Collections in the Current Database列出当前数据库中的集合

To see the list of collections in the current database, use the show collections command:要查看当前数据库中的集合列表，请使用show collections命令：

show collections

The show collections output indicates if a collection is a time series collection or a read-only view.show collections输出指示集合是时间序列集合还是只读视图。

managementFeedback          [view]
survey
weather                     [time-series]
system.buckets.weather
system.views

In the preceding example:在前面的例子中：

• managementFeedback is a view是一个视图
• weather is a time series是一个时间序列
• survey is a collection是一个集合
• system.buckets.weather is a system generated collection that supports the weather time series是支持weather时间序列的系统生成集合
• system.views is a system generated collection that supports views on other collections是系统生成的集合，支持对其他集合的查看

Show Collection Methods显示集合方法

To see the list of methods available on collection objects use the db.<collection>.help() method:要查看集合对象上可用的方法列表，请使用db.<collection>.help()方法：

db.collection.help()

<collection> can be the name of an existing or non-existent collection.可以是现有或不存在的集合的名称。

The output resembles the following abbreviated list:输出类似于以下缩写列表：

Collection Class:

  aggregate          Calculates aggregate values for the data in a collection or a view.
  bulkWrite          Performs multiple write operations with controls for order of execution.
  count              Returns the count of documents that would match a find() query for the collection or view.
  countDocuments     Returns the count of documents that match the query for a collection or view.
  deleteMany         Removes all documents that match the filter from a collection.
  deleteOne          Removes a single document from a collection.
  ...

Show Help for a Specific Collection Method显示特定集合方法的帮助

To see help for a specific collection method in mongosh, use db.<collection>.<method name>, followed by .help or .help().要查看mongosh中特定集合方法的帮助，请使用db.<collection>.<method name>，后跟.help或.help()。

The following example displays help for db.collection.insertOne():以下示例显示db.collection.insertOne()的帮助：

db.collection.insertOne.help()

The output resembles the following:输出类似于以下内容：

db.collection.insertOne(document, options):

Inserts a document into a collection.

For more information on usage: /v8.3/reference/method/db.collection.insertOne

Show Additional Details for a Collection Method显示集合方法的其他详细信息

To see additional details for a collection method type the method name, db.<collection>.<method>, without the parenthesis (()).要查看集合方法的其他详细信息，请键入方法名称db.<collection>.<method>，不带小括号（()）。

The following example returns details about the insertOne() method:以下示例返回insertOne()方法的详细信息：

db.collection.insertOne

The output resembles the following:输出类似于以下内容：

[Function: insertOne] AsyncFunction {
  apiVersions: [ 1, Infinity ],
  serverVersions: [ '3.2.0', '999.999.999' ],
  returnsPromise: true,
  topologies: [ 'ReplSet', 'Sharded', 'LoadBalanced', 'Standalone' ],
  returnType: { type: 'unknown', attributes: {} },
  deprecated: false,
  platforms: [ 0, 1, 2 ],
  isDirectShellCommand: false,
  acceptsRawInput: false,
  shellCommandCompleter: undefined,
  help: [Function (anonymous)] Help
}