Is it possible for a Firestore query using .where() to conduct a search with no results?

Currently, I am in the process of creating a platform where users can upload past exams. Each document contains various fields such as teacher, year, and class, all stored in cloud Firestore. To filter the data by teacher, I am using the .where("Teacher", "==", teacher) method. However, I would like to implement a feature that allows for empty queries so that users can search for multiple math tests from different teachers. Is there a way to achieve this functionality with the .where() operator, or do I need to handle each search case separately?

typescriptfirebaseionic-frameworkgoogle-cloud-firestorequerying

Answer №1

If you want to retrieve all the documents within a collection, you can easily do so by utilizing the get() method found in CollectionReference:

const firestore = firebase.firestore()
const collectionRef = firestore.collection('collection_name')
collectionRef.get().then(querySnapshot => {
    // Access querySnapshot.docs data here
})

A crucial point to note is that a CollectionReference is actually a subclass of Query, meaning it acts as a query without any additional constraints.

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