Firebase数据的服务器端过滤

const firebase = require('firebase/app');
require('firebase/database');

const db = firebase.database();

// 创建一个查询，只获取年龄大于18的用户
const usersRef = db.ref('users');
const query = usersRef.orderByChild('age').startAt(18);

query.once('value', (snapshot) => {
  snapshot.forEach((childSnapshot) => {
    console.log(childSnapshot.key, childSnapshot.val());
  });
});

const query = usersRef.orderByChild('name').equalTo('John Doe');

query.once('value', (snapshot) => {
  snapshot.forEach((childSnapshot) => {
    console.log(childSnapshot.key, childSnapshot.val());
  });
});

const firebase = require('firebase/app');
require('firebase/firestore');

const db = firebase.firestore();

// 创建一个查询，只获取年龄大于18的用户
db.collection('users')
  .where('age', '>', 18)
  .get()
  .then((querySnapshot) => {
    querySnapshot.forEach((doc) => {
      console.log(doc.id, ' => ', doc.data());
    });
  })
  .catch((error) => {
    console.log('Error getting documents: ', error);
  });

db.collection('users')
  .where('age', '>', 18)
  .where('isActive', '==', true)
  .get()
  .then((querySnapshot) => {
    querySnapshot.forEach((doc) => {
      console.log(doc.id, ' => ', doc.data());
    });
  })
  .catch((error) => {
    console.log('Error getting documents: ', error);
  });