删除多个文档

您可以使用以下方式一次删除集合中的多个文档：collection.deleteMany() 方法。传递一个查询文档以指定要删除的集合中的文档子集。如果不提供查询文档（或提供空文档），MongoDB 将匹配集合中的所有文档并将它们删除。虽然可以使用 deleteMany() 删除集合中的所有文档，但请考虑使用 drop() 以获得更好的性能和更清晰的代码。deleteMany() 方法通过传入第二个参数的 options 对象指定更多选项。有关更详细的信息，请参阅 deleteMany() API 文档。

您可以在 deleteMany() 方法的第二个参数传入的 options 对象中指定更多选项。有关更详细的信息，请参阅 deleteMany() API 文档。

示例

以下片段从movies集合中删除多个文档。它使用一个配置查询以匹配和删除标题为“圣诞老人”的电影的查询文档。

注意

您可以使用此示例连接到MongoDB的一个实例并与之交互，以包含示例数据的数据库。有关连接到您的MongoDB实例和加载示例数据集的更多信息，请参阅使用示例指南.

1 // Delete multiple documents
2 
3 import { MongoClient } from "mongodb";
4 
5 // Replace the uri string with your MongoDB deployment's connection string.
6 const uri = "<connection string uri>";
7 
8 const client = new MongoClient(uri);
9 
10 async function run() {
11   try {
12     const database = client.db("sample_mflix");
13     const movies = database.collection("movies");
14 
15     /* Delete all documents that match the specified regular
16     expression in the title field from the "movies" collection */
17     const query = { title: { $regex: "Santa" } };
18     const result = await movies.deleteMany(query);
19 
20     // Print the number of deleted documents
21     console.log("Deleted " + result.deletedCount + " documents");
22   } finally {
23     // Close the connection after the operation completes
24     await client.close();
25   }
26 }
27 // Run the program and print any thrown exceptions
28 run().catch(console.dir);

1 // Delete multiple documents
2 
3 import { MongoClient } from "mongodb";
4 
5 // Replace the uri string with your MongoDB deployment's connection string
6 const uri = "<connection string uri>";
7 
8 const client = new MongoClient(uri);
9 
10 async function run() {
11   try {
12     const database = client.db("sample_mflix");
13     const movies = database.collection("movies");
14 
15     /* Delete all documents that match the specified regular
16     expression in the title field from the "movies" collection */
17     const result = await movies.deleteMany({ title: { $regex: "Santa" } });
18     
19     // Print the number of deleted documents
20     console.log("Deleted " + result.deletedCount + " documents");
21   } finally {
22     // Close the connection after the operation completes
23     await client.close();
24   }
25 }
26 // Run the program and print any thrown exceptions
27 run().catch(console.dir);

首次运行前面的示例时，您将看到以下输出

Deleted 19 documents

如果您多次运行示例，您将看到以下输出，因为在第一次运行中已删除匹配的文档

Deleted 0 documents

删除文档

计数文档

1	// Delete multiple documents
2
3	import { MongoClient } from "mongodb";
4
5	// Replace the uri string with your MongoDB deployment's connection string.
6	const uri = "<connection string uri>";
7
8	const client = new MongoClient(uri);
9
10	async function run() {
11	try {
12	const database = client.db("sample_mflix");
13	const movies = database.collection("movies");
14
15	/* Delete all documents that match the specified regular
16	expression in the title field from the "movies" collection */
17	const query = { title: { $regex: "Santa" } };
18	const result = await movies.deleteMany(query);
19
20	// Print the number of deleted documents
21	console.log("Deleted " + result.deletedCount + " documents");
22	} finally {
23	// Close the connection after the operation completes
24	await client.close();
25	}
26	}
27	// Run the program and print any thrown exceptions
28	run().catch(console.dir);