db.collection.remove()¶

Write Concern写入关注点¶

The remove() method uses the delete command, which uses the default write concern. remove()方法使用delete命令，该命令使用默认的写关注点。To specify a different write concern, include the write concern in the options parameter.要指定不同的写入关注点，请在options参数中包含写入关注点。

Query Considerations查询注意事项¶

By default, remove() removes all documents that match the query expression. 默认情况下，remove()删除与query表达式匹配的所有文档。Specify the justOne option to limit the operation to removing a single document. 指定justOne选项以将操作限制为删除单个文档。To delete a single document sorted by a specified order, use the findAndModify() method.要删除按指定顺序排序的单个文档，请使用findAndModify()方法。

When removing multiple documents, the remove operation may interleave with other read and/or write operations to the collection.删除多个文档时，删除操作可能会与对集合的其他读取和/或写入操作交织。

Capped Collections封顶集合¶

You cannot use the remove() method with a capped collection.不能对封顶集合使用remove()方法。

Sharded Collections分片集合¶

All remove() operations for a sharded collection that specify the justOne: true option must include the shard key or the _id field in the query specification. 指定justOne:true选项的分片集合的所有remove()操作必须包括查询规范中的分片键或_id字段。remove() operations specifying justOne: true in a sharded collection which do not contain either the shard key or the _id field return an error.remove()在不包含分片键或_id字段的分片集合中指定justOne:true的操作将返回错误。

Transactions事务¶

db.collection.remove() can be used inside multi-document transactions.可以在多文档事务中使用。

Do not explicitly set the write concern for the operation if run in a transaction. 如果在事务中运行，请不要显式设置操作的写入关注点。To use write concern with transactions, see Transactions and Write Concern.要将写关注点用于事务，请参阅事务和写关注点。

Remove All Documents from a Collection从集合中删除所有文档¶

To remove all documents in a collection, call the remove method with an empty query document {}. 要删除集合中的所有文档，请使用空查询文档{}调用remove()方法。The following operation deletes all documents from the bios collection:以下操作将从bios集合中删除所有文档：

db.bios.remove( { } )

This operation is not equivalent to the drop() method.此操作与drop()方法不同。

To remove all documents from a collection, it may be more efficient to use the drop() method to drop the entire collection, including the indexes, and then recreate the collection and rebuild the indexes.要从集合中删除所有文档，使用drop()方法删除整个集合（包括索引），然后重新创建集合并重建索引可能会更有效。

Remove All Documents that Match a Condition删除所有符合条件的文档¶

To remove the documents that match a deletion criteria, call the remove() method with the <query> parameter:要删除符合删除条件的文档，请使用<query>参数调用remove()方法：

The following operation removes all the documents from the collection products where qty is greater than 20:以下操作将从products集合中删除qty大于20的所有文档：

db.products.remove( { qty: { $gt: 20 } } )

Override Default Write Concern覆盖默认写关注点¶

The following operation to a replica set removes all the documents from the collection products where qty is greater than 20 and specifies a write concern of "w: majority" with a wtimeout of 5000 milliseconds such that the method returns after the write propagates to a majority of the voting replica set members or the method times out after 5 seconds.对副本集的以下操作将从qty大于20的集合products中删除所有文档，并指定一个"w: majority"的写入关注点，wtimeout为5000毫秒，这样，该方法在写入传播到大多数投票副本集成员后返回，或该方法在5毫秒后超时几秒钟。

db.products.remove(
    { qty: { $gt: 20 } },
    { writeConcern: { w: "majority", wtimeout: 5000 } }
)

Remove a Single Document that Matches a Condition删除符合条件的单个文档¶

To remove the first document that match a deletion criteria, call the remove method with the query criteria and the justOne parameter set to true or 1.要删除与删除条件匹配的第一个文档，请在query条件和justOne参数设置为true或1的情况下调用remove方法。

The following operation removes the first document from the collection products where qty is greater than 20:以下操作将从products集合中删除qty大于20的第一个文档：

db.products.remove( { qty: { $gt: 20 } }, true )

Specify Collation指定排序规则¶

Collation allows users to specify language-specific rules for string comparison, such as rules for lettercase and accent marks.允许用户为字符串比较指定特定于语言的规则，例如字母大小写和重音符号的规则。

A collection myColl has the following documents:myColl集合包含以下文档：

{ _id: 1, category: "café", status: "A" }
{ _id: 2, category: "cafe", status: "a" }
{ _id: 3, category: "cafE", status: "a" }

The following operation includes the collation option:以下操作包括collation选项：

db.myColl.remove(
   { category: "cafe", status: "A" },
   { collation: { locale: "fr", strength: 1 } }
)

Successful Results成功的结果¶

The remove() returns a WriteResult object that contains the status of the operation. remove()返回一个WriteResult对象，该对象包含操作的状态。Upon success, the WriteResult object contains information on the number of documents removed:成功后，WriteResult对象包含有关删除的文档数的信息：

WriteResult({ "nRemoved" : 4 })

Write Concern Errors写关注点错误¶

If the remove() method encounters write concern errors, the results include the WriteResult.writeConcernError field:如果remove()方法遇到写问题错误，结果包括WriteResult.writeConcernError字段：

WriteResult({
  "nRemoved" : 7,
  "writeConcernError" : {
    "code" : 64,
    "codeName" : "WriteConcernFailed",
    "errmsg" : "waiting for replication timed out",
    "errInfo" : {
      "wtimeout" : true,
      "writeConcern" : {    // Added in MongoDB 4.4
        "w" : "majority",
        "wtimeout" : 1,
        "provenance" : "getLastErrorDefaults"
      }
    }
  }
})

Errors Unrelated to Write Concern与写关注点无关的错误¶

If the remove() method encounters a non-write concern error, the results include WriteResult.writeError field:如果remove()方法遇到非写问题错误，结果包括WriteResult.writeError字段：

WriteResult({
   "nRemoved" : 0,
   "writeError" : {
      "code" : 2,
      "errmsg" : "unknown top level operator: $invalidFieldName"
   }
})