firebase 查询 - 查找 map 值在数组中的文档

Question

I'm trying to find the id of a doc where a map value in an array of maps equals "x".

in the following case, I'm trying to find which rep owns the cause with code "hog"

I'll likely be going down the denormalizing route, but is this possible?

Answer 1

Firestore has an array-contains operator that you can use to query whether a certain item exists in an array field , but that operator only works if you specify the exact, complete value of the field. It can't test for a partial match.

The common approach to your use-case is to add an additional array field with just the values you want to query on, ie

cause-codes: ["hog"]

Once you modified your documents with this additional field, you can then use a query like:

repsRef.where('cause-codes:', 'array-contains', 'hof')