CODEWITHSUNDEEP
flutterdartgoogle-cloud-firestore
mac
mac

Reputation: 231

How to add an OR condition to flutter Firebase queries

I am trying to add an OR condition to my flutter firebase query.

Here is my code but I want to check where receiver_name is equal to kim OR sender_name is equal to kim

StreamBuilder( 
  stream: Firestore.instance.collection("payments").where("receiver_name", isEqualTo: userActive).snapshots(),
  builder: (context, snapshot){
 

  return Container ( child:ListView.builder(
      shrinkWrap: true,
    itemCount: snapshot.data.documents.length,
    padding: EdgeInsets.all(0),
    controller: ScrollController(keepScrollOffset: false),
    itemBuilder: (context, index){

      DocumentSnapshot documentSnapshot = snapshot.data.documents[index];

Upvotes: 6

Views: 4859

Answers (2)

Frank van Puffelen
Frank van Puffelen

Reputation: 598797

Update: Since March 2023 OR conditions across multiple fields are possible on Firestore, as shown in the new documentation on OR queries. Be sure to check out the document, including the limitations on queries that use OR clauses.

An example of the syntax for OR conditions:

snapshot = await db.collection('/76015089').where(
  Filter.or(
    Filter("name", isEqualTo: "John"),
    Filter("id", isNotEqualTo: "null"),
  )
).get();
print('Got ${snapshot.docs.length} documents');
for (var doc in snapshot.docs) {
  print(' ${doc.id}: name=${doc.get("name")} id=${doc.get("id")}');
}

For this specific use-case, you can also consider this alternative solution:

Add an array of participants to each document

If you add an array field participants to your documents, with in it the UID fields of the sender and the receiver, you can then use an array-contains query to get all payments in which the user was either the sender or the receiver.

To add a UID to such an array, be sure to use the array-union operator:

documentRef.updateData({"participants": FieldValue.arrayUnion("uidOfUser")});

And then to query it, you'd use:

collectionRef.where('participants', arrayContains: "uidOfUser")

Upvotes: 6

Syed Mahfuzur Rahman
Syed Mahfuzur Rahman

Reputation: 467

OR operator is now available in Firebase.

Its can be achieved now by using Filter.or. Follow this link for more details on it: OR operator

For this you need Cloud Firestore version 24.4.5

in Flutter you need cloud_firestore: ^4.5.0

To query it, you have write like this:

Firestore.instance.collection("payments")
        .where(Filter.or(
            Filter("receiver_name", isEqualTo: "kim"),
            Filter("sender_name", isEqualTo: "kim")
               )).snapshots();

Upvotes: 9

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