An example of what I mean

(ns datascript-example
  (:require [datascript.core :as d]))

(def conn (d/create-conn
           {:location/name  {:db/cardinality :db.cardinality/one
                             :db/unique      :db.unique/identity}
            :location/goods {:db/valueType   :db.type/ref
                             :db/cardinality :db.cardinality/many}

            :symbol {}
            :price  {}}))

(d/transact! conn
             [{:location/name "New York City"
               :location/goods [{:symbol "Cheese"
                                 :price 10}
                                {:symbol "Chocolate"
                                 :price 2}]}])

(ffirst (d/q '[:find (count ?e)
               :where [?e]] @conn))

you declare :location/goods a ref type but :symbol is not unique

symbol isn't unique because different locations can have the same goods in their list of goods, but the prices need to be different

I considered duplicating :location/name on the goods and setting that to be unique but that duplication seems wrong to me

then instead of a vector, could you use a set?

you won't be able to update the price, though

I'll need a unique attribute to update the price, then?

maybe a hash map

{:location/name "New York City"
 :location/goods {"Cheese" {:price 10}}}

idk what your queries are like though

I did a quick test, and I can generate a unique attribute with [symbol location/name] which seems to make the updates work as expected

Make :goods/location instead of :location/goods, and then create a tuple of :goods/location + :goods/symbol and mark that unique