title: I cannot connect Firebase Realtime Database in Vue.js
body: <p>I am trying to connect to Firebase Realtime Database, but I cannot.</p>
  <pre><code>import { initializeApp } from &quot;firebase/app&quot;;
  // Import the functions you need from the SDKs you need
  // TODO: Add SDKs for Firebase products that you want to use
  // https://firebase.google.com/docs/web/setup#available-libraries
  
  // Your web app's Firebase configuration
  const firebaseConfig = {
    apiKey: &quot;AIzaSyDDQLlluO4FusOQ8ucJvD_svdMJE5dkOlw&quot;,
    authDomain: &quot;portfolio-4dd8c.firebaseapp.com&quot;,
    databaseURL: &quot;https://portfolio-4dd8c-default-rtdb.europe-west1.firebasedatabase.app&quot;,
    projectId: &quot;portfolio-4dd8c&quot;,
    storageBucket: &quot;portfolio-4dd8c.appspot.com&quot;,
    messagingSenderId: &quot;237808071168&quot;,
    appId: &quot;1:237808071168:web:006dc98a6c3272fbd39ee5&quot;
  };
   
  // Initialize Firebase
  const app = initializeApp(firebaseConfig);
  </code></pre>
  <p>I import firebase from 'firebase' and app.database(), but it give me an error (app.database() is not a function). I also tried import firebase from 'firebase/app'</p>
  <p>when I write this import firebase from 'firebase',  terminal gives me error below:</p>
  <blockquote>
  <p>This dependency was not found:</p>
  <ul>
  <li>firebase in ./src/main.js</li>
  </ul>
  <p>To install it, you can run: npm install --save firebase
  Error from chokidar (C:): Error: EBUSY: resource busy or locked, lstat 'C:\DumpStack.log.tmp'</p>
  </blockquote>