listCollections

Definition定义

listCollections

Retrieves information, including the names and creation options, for the collections and views in a database.检索数据库中集合和视图的信息，包括名称和创建选项。

The listCollections command returns a document that contains information you can use to create a cursor on the collection.listCollections命令返回一个文档，该文档包含可用于在集合上创建游标的信息。

mongosh provides the db.getCollectionInfos() and the db.getCollectionNames() helper methods.mongosh提供了db.getCollectionInfos()和db.getCollectionNames()辅助方法。

Syntax语法

The command has the following syntax:该命令具有以下语法：

db.runCommand(
   {
     listCollections: 1,
     filter: <document>,
     nameOnly: <boolean>,
     authorizedCollections: <boolean>,
     comment: <any>
   }
)

Command Fields命令字段

The command can take the following optional fields:该命令可以采用以下可选字段：

Behavior行为

Required Access所需访问权限

The listCollections command requires the listCollections action when access control is enforced. 在实施访问控制时，listCollections命令需要listCollections操作。Users must have privileges that grant the listCollections action on the database to run listCollections.用户必须具有对数据库授予listCollections操作的权限才能运行listCollections。

For example, the following command grants the privilege to run db.getCollectionInfos() against the test database:例如，以下命令授予对test数据库运行db.getCollectionInfos()的权限：

{ resource: { db: "test", collection: "" }, actions: [ "listCollections" ] }

The built-in role read provides the privilege to run listCollections for a specific database.内置的角色read提供了为特定数据库运行listCollections的权限。

Users without the required read privilege can run listCollections when authorizedCollections and nameOnly are both set to true. 当authorizedCollections和nameOnly都设置为true时，没有所需read权限的用户可以运行listCollections。In this case, the command returns the names and types for collection(s) where the user has privileges.在这种情况下，该命令返回用户具有权限的集合的名称和类型。

For example, consider a user with a role that grants the following find privilege:例如，考虑具有授予以下find权限的角色的用户：

{ resource: { db: "sales", collection: "currentQuarter" }, actions: [ "find" ] }

The user can run listCollections if authorizedCollections and nameOnly are both set to true.如果authorizedCollections和nameOnly都设置为true，则用户可以运行listCollections。

db.runCommand(
   {
       listCollections: 1.0,
       authorizedCollections: true,
       nameOnly: true
   }
)

The operation returns the name and type of the currentQuarter collection.该操作返回currentQuarter集合的名称和类型。

However, the following operations return an error if the user does not have the required access authorization:但是，如果用户没有所需的访问权限，则以下操作将返回错误：

db.runCommand(
   {
       listCollections: 1.0,
       authorizedCollections: true
   }
)

db.runCommand(
   {
       listCollections: 1.0,
       nameOnly: true
   }
)

db.runCommand(
   {
       listCollections: 1.0,
       authorizedCollections: true,
       nameOnly: true
   }
)

Output输出

listCollections.cursor

A document that contains information with which to create a cursor to documents that contain collection names and options. 包含信息的文档，用于创建指向包含集合名称和选项的文档的游标。The cursor information includes the cursor id, the full namespace for the command, as well as the first batch of results. Each document in the batch output contains the following fields:游标信息包括游标id、命令的完整名称空间以及第一批结果。批处理输出中的每个文档都包含以下字段：

Field字段	Type类型	Description描述
name	String	Name of the collection.集合的名称。
type	String	Type of data store. 数据存储的类型。Returns collection for collections, view for views, and timeseries for time series collection.返回集合的collection、视图的view和时间序列集合的timeseries。
options	Document	Collection options.集合选项。 These options correspond directly to the options available in db.createCollection(). 这些选项直接对应于db.createCollection()中可用的选项。For the descriptions on the options, see db.createCollection(). 有关选项的描述，请参阅db.createCollection()。
info	Document	Lists the following fields related to the collection: 列出与集合相关的以下字段： readOnly boolean. If true the data store is read only.如果为true，则数据存储为只读。 uuid UUID. Once established, the collection UUID does not change. 一旦建立，集合UUID就不会更改。The collection UUID remains the same across replica set members and shards in a sharded cluster.在分片集群中，副本集成员和分片之间的集合UUID保持不变。
idIndex	Document	Provides information on the _id index for the collection.提供有关集合的_id索引的信息。

listCollections.ok

The return value for the command. A value of 1 indicates success.命令的返回值。值为1表示成功。

Example实例

show collections

motorhead
ramones
taylorSwift

db.runCommand(
   {
      listCollections: 1.0,
      nameOnly: true
   }
)

{
  cursor: {
    id: Long("0"),
    ns: 'music.$cmd.listCollections',
    firstBatch: [
      { name: 'motorhead', type: 'collection' },
      { name: 'taylorSwift', type: 'collection' },
      { name: 'ramones', type: 'collection' }
    ]
  },
  ok: 1
}

db.runCommand(
   {
      listCollections: 1.0
   }
)

{
  cursor: {
    id: Long("0"),
    ns: 'music.$cmd.listCollections',
    firstBatch: [
      {
        name: 'motorhead',
        type: 'collection',
        options: {},
        info: {
          readOnly: false,
          uuid: new UUID("09ef1858-2831-47d2-a3a7-9a29a9cfeb94")
        },
        idIndex: { v: 2, key: { _id: 1 }, name: '_id_' }
      },
      {
        name: 'taylorSwift',
        type: 'collection',
        options: {},
        info: {
          readOnly: false,
          uuid: new UUID("6c46c8b9-4999-4213-bcef-9a36b0cff228")
        },
        idIndex: { v: 2, key: { _id: 1 }, name: '_id_' }
      },
      {
        name: 'ramones',
        type: 'collection',
        options: {},
        info: {
          readOnly: false,
          uuid: new UUID("7e1925ba-f2f9-4e42-90e4-8cafd434a6c4")
        },
        idIndex: { v: 2, key: { _id: 1 }, name: '_id_' }
      }
    ]
  },
  ok: 1
}

Learn More了解更多信息

For collection options:对于集合选项：

• db.createCollection()
• create

For collection information:集合信息：

• db.getCollectionInfos()
• mongosh built-in commandsmongosh内置命令