Use ALIAS columns to simplify querying API (#4059)

* Cleanup: remove @api_prop_name_to_db-related cruft

* Use aliases elsewhere in code

lib/plausible/stats/base.ex

@@ -150,25 +150,10 @@ defmodule Plausible.Stats.Base do
     |> filter_by_visit_props(Filters.visit_props(), query)
   end
 
-  @api_prop_name_to_db %{
-    "source" => "referrer_source",
-    "device" => "screen_size",
-    "screen" => "screen_size",
-    "os" => "operating_system",
-    "os_version" => "operating_system_version",
-    "country" => "country_code",
-    "region" => "subdivision1_code",
-    "city" => "city_geoname_id",
-    "entry_page_hostname" => "hostname"
-  }
-
   defp filter_by_visit_props(q, visit_props, query) do
     Enum.reduce(visit_props, q, fn prop_name, sessions_q ->
       filter_key = "visit:" <> prop_name
-
+      db_field = String.to_existing_atom(prop_name)
-      db_field =
-        Map.get(@api_prop_name_to_db, prop_name, prop_name)
-        |> String.to_existing_atom()
 
       from(s in sessions_q,
         where: ^dynamic_filter_condition(query, filter_key, db_field)
@@ -431,7 +416,7 @@ defmodule Plausible.Stats.Base do
     end
   end
 
-  defp db_field_val(:referrer_source, @no_ref), do: ""
+  defp db_field_val(:source, @no_ref), do: ""
   defp db_field_val(:referrer, @no_ref), do: ""
   defp db_field_val(:utm_medium, @no_ref), do: ""
   defp db_field_val(:utm_source, @no_ref), do: ""

lib/plausible/stats/breakdown.ex

@@ -476,41 +476,41 @@ defmodule Plausible.Stats.Breakdown do
   defp do_group_by(q, "visit:source") do
     from(
       s in q,
-      group_by: s.referrer_source,
+      group_by: s.source,
       select_merge: %{
-        source: fragment("if(empty(?), ?, ?)", s.referrer_source, @no_ref, s.referrer_source)
+        source: fragment("if(empty(?), ?, ?)", s.source, @no_ref, s.source)
       },
-      order_by: {:asc, s.referrer_source}
+      order_by: {:asc, s.source}
     )
   end
 
   defp do_group_by(q, "visit:country") do
     from(
       s in q,
-      where: s.country_code != "\0\0" and s.country_code != "ZZ",
+      where: s.country != "\0\0" and s.country != "ZZ",
-      group_by: s.country_code,
+      group_by: s.country,
-      select_merge: %{country: s.country_code},
+      select_merge: %{country: s.country},
-      order_by: {:asc, s.country_code}
+      order_by: {:asc, s.country}
     )
   end
 
   defp do_group_by(q, "visit:region") do
     from(
       s in q,
-      where: s.subdivision1_code != "",
+      where: s.region != "",
-      group_by: s.subdivision1_code,
+      group_by: s.region,
-      select_merge: %{region: s.subdivision1_code},
+      select_merge: %{region: s.region},
-      order_by: {:asc, s.subdivision1_code}
+      order_by: {:asc, s.region}
     )
   end
 
   defp do_group_by(q, "visit:city") do
     from(
       s in q,
-      where: s.city_geoname_id != 0,
+      where: s.city != 0,
-      group_by: s.city_geoname_id,
+      group_by: s.city,
-      select_merge: %{city: s.city_geoname_id},
+      select_merge: %{city: s.city},
-      order_by: {:asc, s.city_geoname_id}
+      order_by: {:asc, s.city}
     )
   end
 
@@ -605,40 +605,40 @@ defmodule Plausible.Stats.Breakdown do
   defp do_group_by(q, "visit:device") do
     from(
       s in q,
-      group_by: s.screen_size,
+      group_by: s.device,
       select_merge: %{
-        device: fragment("if(empty(?), ?, ?)", s.screen_size, @not_set, s.screen_size)
+        device: fragment("if(empty(?), ?, ?)", s.device, @not_set, s.device)
       },
-      order_by: {:asc, s.screen_size}
+      order_by: {:asc, s.device}
     )
   end
 
   defp do_group_by(q, "visit:os") do
     from(
       s in q,
-      group_by: s.operating_system,
+      group_by: s.os,
       select_merge: %{
-        os: fragment("if(empty(?), ?, ?)", s.operating_system, @not_set, s.operating_system)
+        os: fragment("if(empty(?), ?, ?)", s.os, @not_set, s.os)
       },
-      order_by: {:asc, s.operating_system}
+      order_by: {:asc, s.os}
     )
   end
 
   defp do_group_by(q, "visit:os_version") do
     from(
       s in q,
-      group_by: [s.operating_system, s.operating_system_version],
+      group_by: [s.os, s.os_version],
       select_merge: %{
-        os: fragment("if(empty(?), ?, ?)", s.operating_system, @not_set, s.operating_system),
+        os: fragment("if(empty(?), ?, ?)", s.os, @not_set, s.os),
         os_version:
           fragment(
             "if(empty(?), ?, ?)",
-            s.operating_system_version,
+            s.os_version,
             @not_set,
-            s.operating_system_version
+            s.os_version
           )
       },
-      order_by: {:asc, s.operating_system_version}
+      order_by: {:asc, s.os_version}
     )
   end