Question 120089 in Firebase Question posted in
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Firebase – UNABLE TO Get multiple documents from a collection FROM FIRESTORE

I have coded the below snippet from firestore site and according to my database
but the code isn`t working
i have tried too but nothing else works

the WHERE condition is the main reason isn`t working
else it works fine

 const test =() =>{
    try {
      dob.collection("users")
      .where("F_name", "==", true)
    .get()
    .then((querySnapshot) => {
        querySnapshot.forEach((doc) => {
            console.log(doc.id, " => ", doc.data());
        });
    })
    .catch((error) => {
        console.log("Error getting documents: ", error);
    });
    } catch{
      console.log("Erroror")
    }
  }

Database structure:

enter image description here

Tags:

3

Answers


  1. Chosen as BEST ANSWER
    0

    I have edited and works fine, but i want to add that list of email_id in the dropdown but doesn`t works

      var email_user=[];
  const [open, setOpen] = useState(false);
  const [value, setValue] = useState(null);
  const [items, setItems] = useState(email_user);

    try {
      dob.collection("users")
      .where('email_id', '!=', "")
      .get()    
    .then((querySnapshot) => {
        querySnapshot.forEach((doc, i) => {
            // console.log(doc.id, " => ", doc.data());
            console.log(doc.data().email_id)
            for (let i = 0; i < doc.data().length; i++) {
              email_user[i] = doc.data().email_id[i];
              console.log("email_user : ", email_user[i])
            }
        });
    })
    .catch((error) => {
        console.log("Error getting documents: ", error);
    });
    } catch{
      console.log("Error")
    }
   
      



       <DropDownPicker
        open={open}
        value={value}
        items={items}
        setOpen={setOpen}
        setValue={setValue}
        setItems={setItems}
      />

    enter image description here


  2. 0

    As per the document data, the F_name field’s value is a string but you are trying to find a boolean value with where("F_name", "==", true).

    The data type must be same when using queries. Try:

    dob.collection("users").where("F_name", "==", "asdf11")

    Here the value is hard-coded but even if you want to pass user’s input in the query, then you can pass a variable with string value.

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  3. 0

    If you want to fetch all users from the database you can just do a get without any query. But it’s probably not what you want.

    dob.collection("users").get()

    If you are looking for several user name values you can use the in operator (https://firebase.google.com/docs/firestore/query-data/queries#in_not-in_and_array-contains-any)

    dob.collection.where('F_name', 'in', ['asdf11', 'asdf123']).get();

    If you are looking for users that has a provided a value for the F_name field, then you can use the != operator: https://firebase.google.com/docs/firestore/query-data/queries#not_equal_

    // If you store it as null when name is not set
dob.collection.where('F_name', '!=', null).get();

// If you store it as empty string when name is not set
dob.collection.where('F_name', '!=', '').get();
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