通过用户ID和日期范围查询Firestore？

Question

I need to query Firestore, but it keeps telling me I need an index. Problem is that isn't realistic, since EVERY user would require a custom index based on their UserId. For security, I can't allow anyone access unless canAccess.${userID} == true as in the example below. But if I were to take ALL items, and filter them by date client-side I would be fetching hundreds of thousands of items every time I change the date range, so it isn't practical.

this.db.collection('items')
       .where(`canAccess.${userId}`, '==', true)
       .where('date', '>=', startDate)
       .where('date', '<=', endDate);

How would one going about fetching only the items they are allowed to access, and only between the chosen date range?

Answer 1

You'll have to restructure your documents in order to perform this query. Consider putting the uids that can access the document in a field with a List type called canAccess . Then query the list with array-contains after you create an index on that field.

this.db.collection('items')
       .where('canAccess', 'array-contains', userId)
       .where('date', '>=', startDate)
       .where('date', '<=', endDate);