arrayUnion do in Firebase Firestore?arrayUnion adds elements to an array field in a document only if they are not already present. It prevents duplicates.
arrayRemove in Firebase Firestore?arrayRemove removes all instances of specified elements from an array field in a document.
arrayUnion add multiple elements at once?Yes, you can pass multiple elements to arrayUnion and it will add all unique ones to the array.
arrayRemove with an element not in the array?Nothing changes. arrayRemove only removes elements if they exist; if not, the array stays the same.
arrayUnion and arrayRemove useful compared to reading and writing the whole array?<p>They let you update arrays atomically without overwriting the entire array, avoiding conflicts and saving bandwidth.</p>arrayUnion adds unique elements to an array field, preventing duplicates.
arrayRemove do if the element is not in the array?arrayRemove only removes elements if they exist; otherwise, it does nothing.
arrayUnion at once?arrayUnion accepts multiple elements and adds all unique ones.
arrayUnion instead of reading and rewriting the whole array?arrayUnion updates arrays atomically, avoiding overwriting and conflicts.
arrayRemove removes all instances of specified elements from an array.
arrayUnion and arrayRemove help manage array fields in Firebase Firestore.arrayUnion would be better than rewriting the entire array.