A simple where clause in flutter/firebase database - firebase

Question

Today I started experimenting with Firebase Live database. Maybe I'm thinking too much in sql terms. But what I want to do is get a record from my database where a value equals a variable with flutter. My table looks like this:
What I'm trying to achieve is something like this:
FirebaseDatabase.instance.reference().child('users').where('User_id', 1508)
Like I said. I'm a complete beginner when it comes to Live Databases.
I hope someone can help me with this issue I'm having.
Kind regards,
Namanix

Answer 1

According to firstore docs
Firestore.instance
.collection('talks')
.where("topic", isEqualTo: "flutter")
.snapshots()
.listen((data) =>
data.documents.forEach((doc) => print(doc["title"])));

Answer 2

If you have the user id in a variable for example called:
String uid = currentUser.uid;
then you can do the following:
FirebaseDatabase.instance.reference().child('users/$uid')
Update
I think this is what you are asking about
FirebaseDatabase.instance
.reference().child("users")
.orderByChild("User_id")
.equalTo($this.userId)

Answer 3

#override
Widget build(BuildContext context) {
return Scaffold(
body: Center(
child: FutureBuilder<QuerySnapshot>(
future: FirebaseFirestore
.instance
.collection('users')
.where("user_id", isEqualTo: FirebaseAuth.instance.currentUser!.uid)// 👈 Your where condition here
.get(),
builder: (_, snapshot) {
if (snapshot.hasError) return Text('Error = ${snapshot.error}');
if (snapshot.connectionState == ConnectionState.waiting) {
return const Text("Loading");
}
return ListView(
children: snapshot.data!.docs.map((DocumentSnapshot document) {
Map<String, dynamic> data = document.data()! as Map<String, dynamic>;
return ListTile(
title: Text(data['avatar']), // 👈 Your valid data here
);
}).toList());
},
)),
);
}
Also refer: How to use StreamBuilder and FutureBuilder for single and multiple documents