Add option to turn JSON column unfolding off (boat161) (#22997)

Adds option to turn JSON column unfolding off. This does not constitute an actual fix of boat161 but flamber wanted it

src/metabase/driver/postgres.clj

@@ -39,7 +39,7 @@
 
 (driver/register! :postgres, :parent :sql-jdbc)
 
-(defmethod driver/database-supports? [:postgres :nested-field-columns] [_ _ _] true)
+(defmethod driver/database-supports? [:postgres :nested-field-columns] [_ _ database] (get-in database [:details :json-unfolding]))
 
 ;;; +----------------------------------------------------------------------------------------------------------------+
 ;;; |                                             metabase.driver impls                                              |
@@ -161,6 +161,12 @@
      :visible-if   {"ssl-use-client-auth" true}}
     driver.common/ssh-tunnel-preferences
     driver.common/advanced-options-start
+    {:name         "json-unfolding"
+     :display-name (trs "Unfold JSON Columns")
+     :type         :boolean
+     :visible-if   {"advanced-options" true}
+     :description  (trs "We unfold JSON columns into component fields. This is on by default but you can turn it off if performance is slow.")
+     :default      true}
     (assoc driver.common/additional-options
            :placeholder "prepareThreshold=0")
     driver.common/default-advanced-options]

test/metabase/driver/postgres_test.clj

@@ -295,7 +295,8 @@
   (mt/test-driver :postgres
     (testing "json breakouts and order bys have alias coercion"
       (drop-if-exists-and-create-db! "json-alias-test")
-      (let [details   (mt/dbdef->connection-details :postgres :db {:database-name "json-alias-test"})
+      (let [details   (mt/dbdef->connection-details :postgres :db {:database-name "json-alias-test"
+                                                                   :json-unfolding true})
             spec      (sql-jdbc.conn/connection-details->spec :postgres details)
             json-part (json/generate-string {:bob :dobbs})
             insert    (str "CREATE TABLE json_alias_test (json_part JSON NOT NULL);"
@@ -325,7 +326,8 @@
   (mt/test-driver :postgres
     (testing "describes json columns and gives types for ones with coherent schemas only"
       (drop-if-exists-and-create-db! "describe-json-test")
-      (let [details (mt/dbdef->connection-details :postgres :db {:database-name "describe-json-test"})
+      (let [details (mt/dbdef->connection-details :postgres :db {:database-name "describe-json-test"
+                                                                 :json-unfolding true})
             spec    (sql-jdbc.conn/connection-details->spec :postgres details)]
         (jdbc/with-db-connection [conn (sql-jdbc.conn/connection-details->spec :postgres details)]
           (jdbc/execute! spec [(str "CREATE TABLE describe_json_table (coherent_json_val JSON NOT NULL, incoherent_json_val JSON NOT NULL);"
@@ -383,7 +385,8 @@
   (mt/test-driver :postgres
     (testing "sync goes and runs with identifier if there is a schema other than default public one"
       (drop-if-exists-and-create-db! "describe-json-with-schema-test")
-      (let [details (mt/dbdef->connection-details :postgres :db {:database-name "describe-json-with-schema-test"})
+      (let [details (mt/dbdef->connection-details :postgres :db {:database-name "describe-json-with-schema-test"
+                                                                 :json-unfolding true})
             spec    (sql-jdbc.conn/connection-details->spec :postgres details)]
         (jdbc/with-db-connection [conn (sql-jdbc.conn/connection-details->spec :postgres details)]
           (jdbc/execute! spec [(str "CREATE SCHEMA bobdobbs;"
@@ -405,7 +408,8 @@
   (mt/test-driver :postgres
     (testing "blank out if huge. blank out instead of silently limiting"
       (drop-if-exists-and-create-db! "big-json-test")
-      (let [details  (mt/dbdef->connection-details :postgres :db {:database-name "big-json-test"})
+      (let [details  (mt/dbdef->connection-details :postgres :db {:database-name "big-json-test"
+                                                                  :json-unfolding true})
             spec     (sql-jdbc.conn/connection-details->spec :postgres details)
             big-map  (into {} (for [x (range 300)] [x :dobbs]))
             big-json (json/generate-string big-map)