Bulk.find.arrayFilters() (mongosh method方法)

Description描述

Bulk.find.arrayFilters(<array of filter documents>)

Determines which array elements to modify for an update operation on an array field:确定在数组字段上进行更新操作时要修改哪些数组元素：

Bulk.find(<query>).arrayFilters([ <filter1>, ... ]).updateOne(<update>);
Bulk.find(<query>).arrayFilters([ <filter1>, ... ]).update(<update>);

In the update document, use the $[<identifier>] filtered positional operator to define an identifier, which you then reference in the array filter documents. 在更新文档中，使用$[<identifier>]筛选位置运算符定义一个标识符，然后在数组筛选文档中引用该标识符。You cannot have an array filter document for an identifier if the identifier is not included in the update document.如果标识符未包含在更新文档中，则无法为标识符创建数组筛选器文档。

The <identifier> must begin with a lowercase letter and contain only alphanumeric characters.<identifier>必须以小写字母开头，并且只能包含字母数字字符。

You can include the same identifier multiple times in the update document; however, for each distinct identifier ($[identifier]) in the update document, you must specify exactly one corresponding array filter document. 您可以在更新文档中多次包含相同的标识符；但是，对于更新文档中的每个不同标识符（$[identifier]），您必须指定一个相应的数组筛选器文档。That is, you cannot specify multiple array filter documents for the same identifier. For example, if the update statement includes the identifier x (possibly multiple times), you cannot specify the following for arrayFilters that includes 2 separate filter documents for x:也就是说，不能为同一标识符指定多个数组筛选器文档。例如，如果更新语句包含标识符x（可能多次），则不能为包含2个单独的x筛选文档的arrayFilters指定以下内容：

// INVALID

[
  { "x.a": { $gt: 85 } },
  { "x.b": { $gt: 80 } }
]

However, you can specify compound conditions on the same identifier in a single filter document, such as in the following examples:但是，您可以在单个筛选器文档中为同一标识符指定复合条件，例如以下示例：

// Example 1
[
  { $or: [{"x.a": {$gt: 85}}, {"x.b": {$gt: 80}}] }
]
// Example 2
[
  { $and: [{"x.a": {$gt: 85}}, {"x.b": {$gt: 80}}] }
]
// Example 3
[
  { "x.a": { $gt: 85 }, "x.b": { $gt: 80 } }
]

Append to Bulk.find() method to specify the array filters for the updateOne() and update() operations.附加到Bulk.find()方法，为updateOne()和update()操作指定数组筛选器。

Compatibility兼容性

This command is available in deployments hosted in the following environments:此命令在以下环境中托管的部署中可用：

• MongoDB Atlas: The fully managed service for MongoDB deployments in the cloud：云中MongoDB部署的完全托管服务

Example示例

var bulk = db.coll.initializeUnorderedBulkOp();
bulk.find({}).arrayFilters( [ { "elem.grade": { $gt: 85 } } ] ).updateOne( { $set: { "grades.$[elem].mean" : 70 } } );
bulk.execute();