orderByChild is not a function-CodePudding

i am trying to fetch filtered data from my firebase database in reactjs web application.i do it as follow, but it gives this error that..orderByChild is not a functionwhat's going on, i cants understand.

import fb from '../../firebase';
const DB =fb.firestore();
const restro_list = DB.collection('restros');
const[restros, Setrestros] = useState([]);

useEffect(()=>{
    const unsubrestro = restro_list.orderByChild('MealType').on('value', snapshot => {
       snapshot.forEach(docu => {
          const data = docu.docs.forEach(doc => ({
             ...doc.val(),
             id: doc.id,
           }));
           Setrestros(data);
        });
   });
   return unsubrestro;
 },[]);

but this always give me error.

CodePudding user response：

The orderByChild() is a function in Firebase Realtime Database SDK but you are using Firestore where you should use orderBy() as shown below:

const unsubrestro = restro_list.orderBy("MealType").onSnapshot((snapshot) => {
  const data = snapshot.docs.map((d) => ({ id: d.id, ...d.data() }))
  Setrestros(data);
})