Firestore search array contains for multiple values

Question

If I have a simple collection such as:

Fruits:
  Banana:
   title: \"Banana\"
   vitamins: [\"potassium\",\"B6\",\"C\"]
  Apple:
   title: \"Apple\"
   vitam         


        

Answer 1

It would be tempting to to look for documents that match multiple conditions, by chaining the conditions in the query:

db.collection("Fruits")
    .whereField("vitamins", arrayContains: "B6")
    .whereField("vitamins", arrayContains: "C")

But the documentation on compound queries suggests that you cannot currently have multiple arrayContains conditions in a single query.

So, it is not possible with what you have today. Consider instead using a map structure instead of an array:

Fruits:
  Banana:
   title: "Banana"
   vitamins: {
     "potassium": true,
     "B6": true,
     "C": true
   }

Then you could query like this:

db.collection("Fruits")
    .whereField("vitamins.B6", isEqualTo: true)
    .whereField("vitamins.C", isEqualTo: true)