MongoDB如何存储大文本数据？

MongoDB提供了多种存储大文本数据的方法，以下是其中的两种：

1.使用GridFS存储大文本数据

GridFS是MongoDB提供的一种存储大文件的方式。它将文件的内容切分成多个chunk（块），然后分别存储在两个集合中：一个存储文件的元数据（文件名、大小、上传时间等），另一个存储文件的chunk数据。对于较大的文件，可以将其分成多个chunk存储，从而减轻对系统的负载。

下面是使用GridFS存储和读取文件的示例代码：

// 存储文件 const fs = require('fs'); const { MongoClient } = require('mongodb');

async function saveFile(filePath, dbName, bucketName) { const client = await MongoClient.connect('mongodb://localhost:27017', { useNewUrlParser: true }); const db = client.db(dbName); const bucket = new db.GridFSBucket(bucketName); const readStream = fs.createReadStream(filePath); const uploadStream = bucket.openUploadStream('file.txt'); readStream.pipe(uploadStream); return new Promise((resolve) => { uploadStream.on('finish', () => { client.close(); resolve('File saved successfully!'); }); }); }

// 读取文件 async function readFile(dbName, bucketName) { const client = await MongoClient.connect('mongodb://localhost:27017', { useNewUrlParser: true }); const db = client.db(dbName); const bucket = new db.GridFSBucket(bucketName); const downloadStream = bucket.openDownloadStreamByName('file.txt'); const chunks = []; downloadStream.on('data', (chunk) => { chunks.push(chunk); }); return new Promise((resolve) => { downloadStream.on('end', () => { client.close(); resolve(Buffer.concat(chunks).toString()); }); }); }

saveFile('/path/to/file.txt', 'myDB', 'myBucket').then(() => { readFile('myDB', 'myBucket').then((fileContent) => { console