How do I query Cloud Firestore for an array that matches all values, but in any order?

user_11015833 0
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I have an array in Firestore in different documents like this:

Colors: [Blue, Red, Green]

I want to query to find the documents that matches my input, Colors: [Red, Green, Blue]. But it should NOT return documents that contain more than that, i.e. [Blue, Red, Green, Yellow]. It has to be an exact match, but I do not necessarily know the order of the items in the array. Is this even possible?

google-cloud-firestore
2 Answers

First, add a field to each document that contains the array length so that you can filter based on the array length. Then create a compound query for arrays with the correct length, with an "array-contains" clause for each color.

Note that the particular array you are searching for must not contain any duplicate elements or this method will not work correctly.

user_33988390

What you're asking is not possible with a single query with the data you have now. You will either have to:

  1. Ensure the order of the array so you can use an equality filter providing an array that contains the exact same data.
  2. Rewrite the array to a map, so you could instead use an equality filter for the same set of key/value pairs. (The keys could be the colors, and the values could simply be boolean true.)
user_8071260
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