Replace a Document替换一个文档

You can replace a single document using the collection.replaceOne() method. 您可以使用collection.replaceOne()方法替换单个文档。replaceOne() accepts a query document and a replacement document. 接受查询文档和替换文档。If the query matches a document in the collection, it replaces the first document that matches the query with the provided replacement document. 如果查询与集合中的某个文档匹配，它将用提供的替换文档替换与查询匹配的第一个文档。This operation removes all fields and values in the original document and replaces them with the fields and values in the replacement document. 此操作将删除原始文档中的所有字段和值，并将其替换为替换文档中的字段和值。The value of the _id field remains the same unless you explicitly specify a new value for _id in the replacement document._id字段的值保持不变，除非在替换文档中显式指定_id的新值。

You can specify additional options, such as upsert, using the optional options parameter. 您可以使用可选options参数指定其他选项，例如upsert。If you set the upsert option field to true the method inserts a new document if no document matches the query.如果将upsert选项字段设置为true，则如果没有与查询匹配的文档，则该方法将插入新文档。

The replaceOne() method throws an exception if an error occurs during execution. 如果在执行过程中发生错误，replaceOne()方法将引发异常。For example, if you specify a value that violates a unique index rule, replaceOne() throws a duplicate key error.例如，如果指定的值违反了唯一索引规则，replaceOne()将抛出duplicate key error。

import { MongoClient } from "mongodb";

// Replace the uri string with your MongoDB deployment's connection string.将uri字符串替换为MongoDB部署的连接字符串。
const uri = "<connection string uri>";

const client = new MongoClient(uri);

async function run() {
  try {
    const database = client.db("sample_mflix");
    const movies = database.collection("movies");

    // create a query for a movie to update为要更新的电影创建查询
    const query = { title: { $regex: "The Cat from" } };
    // create a new document that will be used to replace the existing document创建一个新文档，用于替换现有文档
    const replacement = {
      title: `The Cat from Sector ${Math.floor(Math.random() * 1000) + 1}`,
    };

    const result = await movies.replaceOne(query, replacement);
    console.log(`Modified ${result.modifiedCount} document(s)`);
  } finally {
    await client.close();
  }
}
run().catch(console.dir);

Modified 1 document(s)