Merge pull request #5982 from metabase/fix-fingerprinting-overflow

Fix integer overflow in average

src/metabase/sync/analyze/fingerprint/number.clj

 (ns metabase.sync.analyze.fingerprint.number
   "Logic for generating a `NumberFingerprint` from a sequence of values for a `:type/Number` Field."
-  (:require [metabase.sync.interface :as i]
+  (:require [kixi.stats.core :as stats]
+            [metabase.sync.interface :as i]
             [schema.core :as s]))
 
-(s/defn ^:private ^:always-validate average :- s/Num
-  "Return the average of VALUES."
-  [values :- i/FieldSample]
-  (/ (double (reduce + values))
-     (double (count values))))
-
 (s/defn ^:always-validate number-fingerprint :- i/NumberFingerprint
   "Generate a fingerprint containing information about values that belong to a `:type/Number` Field."
   [values :- i/FieldSample]
   {:min (apply min values)
    :max (apply max values)
-   :avg (average values)})
+   :avg (transduce (map double) stats/mean values)})

test/metabase/sync/analyze/fingerprint/number_test.clj

+(ns metabase.sync.analyze.fingerprint.number-test
+  (:require [expectations :refer :all]
+            [metabase.sync.analyze.fingerprint.number :as number]))
+
+(expect
+  (approximately (double Long/MAX_VALUE))
+  (:avg (number/number-fingerprint [Long/MAX_VALUE Long/MAX_VALUE])))