Firestore Tag Filtering With in Queries Query by tag or category labels in Firestore using IN and array-contains-any. 223 words. By Jeff Delaney Created Nov 13, 2019 Last Updated Nov 13, 2019 Slack #firebase #firestore Health Check firebase@7.3.0 With the release of the Firebase JS SDK version 7.3.0, we now have the ability to perform IN queries. It provides two new options to use with the where method, including in and array-contains-any. A common use-case is tag or category filtering. For example, you may want to display a set of checkboxes, then run an inclusive query for any results that contain at least 1 checkbox. Firestore IN Query Option 1 - Document has ONE Tag If the document can only have one tag or category at a time, you are likely looking for an in query. It takes an array of values (limited to a max of 10), then returns all matching documents. It is not perfectly analogous to SQL and you can also think of it as a logical OR query, i.e. all documents where color == red OR white OR blue Data format for IN query file_type_js_official in.js const db = firebase.firestore(); const ref = db.collection('products'); const query = ref.where('color', 'in', ['red', 'white', 'blue']); Option 2 - Document has MANY Tags In other cases, your documents may be tagged with many values in an array. You fetch all documents that have a at least one value in the array with array-contains-any. Data format for array-contains-any query file_type_js_official firestore.js const query = ref.where('colors', 'array-contains-any', ['red', 'white', 'blue']); Simple, yet powerful!