I am reading some data from Firebase's Cloud Firestore but I've seen several ways to do it. The example I saw used the get and onSnapshot function like this:
db.collection("cities").doc("SF")
.onSnapshot(doc => {
console.log(doc.data());
});
or this
var docRef = db.collection("cities").doc("SF");
docRef.get().then(doc => {
if (doc.exists) {
console.log("Document data:", doc.data());
} else {
console.log("No such document!");
}
}).catch(function(error) {
console.log("Error getting document:", error);
});
Is there any difference between them?
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