How to delete several records in MongoDB using NodeJS

To achieve this we will use MongoDB driver (npm i mongodb), promise and the deleteMany method. The following code will find all the documents with a field this and a value equal to 1. Node that we copy the parameter ok in db1 otherwise, the database object would not be accessible from the subsequent blocks. For example, ok.close() would not work.

const MongoClient = require('mongodb').MongoClient;
// Connection url
const url = 'mongodb://192.168.1.203:27017';
options = {
    useNewUrlParser: true
};

MongoClient.connect(url, options).then(function (ok) {
        
       db1 = ok;
       dbName = 'testdb';
        return db1.db(dbName).collection('test').deleteMany({"this":1});

    })
    .then(function (dbs) {
console.log(dbs);
db1.close();
    });

In the mongo shell, after selecting the database (use testdb), there is no records left because it deleted all the documents in which there was “this”:1 We ran the command before and after running the NodeJS code.

MongoDB Enterprise > db.test.find()
{ "_id" : ObjectId("5bab61018df000e560655d2d"), "this" : 1, "another" : "this is a test" }
{ "_id" : ObjectId("5bab6110b8724ae561d7191d"), "this" : 1, "another" : "this is a test" }
MongoDB Enterprise > db.test.find()
MongoDB Enterprise > 

The deleteMany method returns an object which is dbs in our code. The result is the following:

CommandResult {
  result: { n: 2, ok: 1 },
  connection:
   Connection {
     domain: null,
     _events:
      { error: [Object],
        close: [Object],
        timeout: [Object],
        parseError: [Object] },
     _eventsCount: 4,
     _maxListeners: undefined,
     options:
      { host: '192.168.1.203',
        port: 27017,
        size: 5,
        minSize: 0,
        connectionTimeout: 30000,
        socketTimeout: 360000,
        keepAlive: true,
        keepAliveInitialDelay: 300000,
        noDelay: true,
        ssl: false,
        checkServerIdentity: true,
        ca: null,
        crl: null,
        cert: null,
        key: null,
        passPhrase: null,
        rejectUnauthorized: false,
        promoteLongs: true,
        promoteValues: true,
        promoteBuffers: false,
        reconnect: true,
        reconnectInterval: 1000,
        reconnectTries: 30,
        domainsEnabled: false,
        disconnectHandler: [Object],
        cursorFactory: [Object],
        emitError: true,
        monitorCommands: false,
        promiseLibrary: [Function: Promise],
        clientInfo: [Object],
        servers: [Array],
        useNewUrlParser: true,
        db: 'admin',
        dbName: 'admin',
        socketTimeoutMS: 360000,
        connectTimeoutMS: 30000,
        bson: BSON {} },
     id: 0,
     logger: Logger { className: 'Connection' },
     bson: BSON {},
     tag: undefined,
     messageHandler: [Function],
     maxBsonMessageSize: 67108864,
     port: 27017,
     host: '192.168.1.203',
     family: undefined,
     keepAlive: true,
     keepAliveInitialDelay: 300000,
     noDelay: true,
     connectionTimeout: 30000,
     socketTimeout: 360000,
     destroyed: false,
     domainSocket: false,
     singleBufferSerializtion: true,
     serializationFunction: 'toBinUnified',
     ca: null,
     crl: null,
     cert: null,
     key: null,
     passphrase: null,
     ciphers: null,
     ecdhCurve: null,
     ssl: false,
     rejectUnauthorized: false,
     checkServerIdentity: true,
     responseOptions:
      { promoteLongs: true,
        promoteValues: true,
        promoteBuffers: false },
     flushing: false,
     queue: [],
     connection:
      Socket {
        connecting: false,
        _hadError: false,
        _handle: [Object],
        _parent: null,
        _host: null,
        _readableState: [Object],
        readable: true,
        domain: null,
        _events: [Object],
        _eventsCount: 6,
        _maxListeners: undefined,
        _writableState: [Object],
        writable: true,
        allowHalfOpen: false,
        _bytesDispatched: 434,
        _sockname: null,
        _pendingData: null,
        _pendingEncoding: '',
        server: null,
        _server: null,
        _idleTimeout: 360000,
        _idleNext: [Object],
        _idlePrev: [Object],
        _idleStart: 303,
        _destroyed: false,
        [Symbol(asyncId)]: 5,
        [Symbol(bytesRead)]: 0,
        [Symbol(asyncId)]: 8,
        [Symbol(triggerAsyncId)]: 1 },
     writeStream: null,
     hashedName: 'ecc4c59c3c6dde71259f7aabc040337c19f4b64c',
     workItems: [],
     buffer: null,
     sizeOfMessage: 0,
     bytesRead: 0,
     stubBuffer: null },
  message:
   Response {
     parsed: true,
     raw: <Buffer 3c 00 00 00 6d 64 00 00 02 00 00 00 01 00 00 00 08 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 01 00 00 00 18 00 00 00 10 6e 00 02 00 00 00 01 6f 6b ... >,
     data: <Buffer 08 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 01 00 00 00 18 00 00 00 10 6e 00 02 00 00 00 01 6f 6b 00 00 00 00 00 00 00 f0 3f 00>,
     bson: BSON {},
     opts:
      { promoteLongs: true,
        promoteValues: true,
        promoteBuffers: false },
     length: 60,
     requestId: 25709,
     responseTo: 2,
     opCode: 1,
     fromCompressed: undefined,
     responseFlags: 8,
     cursorId: Long { _bsontype: 'Long', low_: 0, high_: 0 },
     startingFrom: 0,
     numberReturned: 1,
     documents: [ [Object] ],
     cursorNotFound: false,
     queryFailure: false,
     shardConfigStale: false,
     awaitCapable: true,
     promoteLongs: true,
     promoteValues: true,
     promoteBuffers: false,
     index: 44,
     hashedName: 'ecc4c59c3c6dde71259f7aabc040337c19f4b64c' },
  deletedCount: 2 }