lib/mv/membership/member_export/build.ex

@@ -244,9 +244,15 @@ defmodule Mv.Membership.MemberExport.Build do
   defp maybe_sort(query, _field, nil), do: {query, false}
 
   defp maybe_sort(query, field, order) when is_binary(field) do
-    if custom_field_sort?(field) do
+    cond do
+      field == "groups" ->
+        # Groups sort → in-memory nach dem Read (wie Tabelle)
         {query, true}
-    else
+
+      custom_field_sort?(field) ->
+        {query, true}
+
+      true ->
         field_atom = String.to_existing_atom(field)
 
         if field_atom in (Mv.Constants.member_fields() -- [:notes]) do
@@ -263,6 +269,9 @@ defmodule Mv.Membership.MemberExport.Build do
     do: []
 
   defp sort_members_by_custom_field(members, field, order, custom_fields) when is_binary(field) do
+    if field == "groups" do
+      sort_members_by_groups_export(members, order)
+    else
       id_str = String.trim_leading(field, @custom_field_prefix)
       custom_field = Enum.find(custom_fields, fn cf -> to_string(cf.id) == id_str end)
 
@@ -279,6 +288,27 @@ defmodule Mv.Membership.MemberExport.Build do
       |> Enum.sort(fn {_, ka}, {_, kb} -> MemberExportSort.key_lt(ka, kb, order) end)
       |> Enum.map(fn {m, _} -> m end)
     end
+  end
+
+  defp sort_members_by_groups_export(members, order) do
+    # Members with groups first, then by first group name alphabetically (min = first by sort order)
+    # Match table behavior from MvWeb.MemberLive.Index.sort_members_by_groups/2
+    first_group_name = fn member ->
+      (member.groups || [])
+      |> Enum.map(& &1.name)
+      |> Enum.min(fn -> nil end)
+    end
+
+    members
+    |> Enum.sort_by(fn member ->
+      name = first_group_name.(member)
+      # Nil (no groups) sorts last in asc, first in desc
+      {name == nil, name || ""}
+    end)
+    |> then(fn list ->
+      if order == "desc", do: Enum.reverse(list), else: list
+    end)
+  end
 
   defp find_cfv(member, custom_field) do
     (member.custom_field_values || [])

lib/mv_web/controllers/member_export_controller.ex

@@ -341,10 +341,16 @@ defmodule MvWeb.MemberExportController do
   defp maybe_sort_export(query, _field, nil), do: {query, false}
 
   defp maybe_sort_export(query, field, order) when is_binary(field) do
-    if custom_field_sort?(field) do
+    cond do
+      field == "groups" ->
+        # Groups sort → in-memory nach dem Read (wie Tabelle)
+        {query, true}
+
+      custom_field_sort?(field) ->
         # Custom field sort → in-memory nach dem Read (wie Tabelle)
         {query, true}
-    else
+
+      true ->
         field_atom = String.to_existing_atom(field)
 
         if field_atom in (Mv.Constants.member_fields() -- [:notes]) do
@@ -370,6 +376,10 @@ defmodule MvWeb.MemberExportController do
   defp sort_members_by_custom_field_export(members, field, order, custom_fields)
        when is_binary(field) do
     order = order || "asc"
+
+    if field == "groups" do
+      sort_members_by_groups_export(members, order)
+    else
       id_str = String.trim_leading(field, @custom_field_prefix)
 
       custom_field =
@@ -398,6 +408,27 @@ defmodule MvWeb.MemberExportController do
         sorted_with_values ++ without_values
       end
     end
+  end
+
+  defp sort_members_by_groups_export(members, order) do
+    # Members with groups first, then by first group name alphabetically (min = first by sort order)
+    # Match table behavior from MvWeb.MemberLive.Index.sort_members_by_groups/2
+    first_group_name = fn member ->
+      (member.groups || [])
+      |> Enum.map(& &1.name)
+      |> Enum.min(fn -> nil end)
+    end
+
+    members
+    |> Enum.sort_by(fn member ->
+      name = first_group_name.(member)
+      # Nil (no groups) sorts last in asc, first in desc
+      {name == nil, name || ""}
+    end)
+    |> then(fn list ->
+      if order == "desc", do: Enum.reverse(list), else: list
+    end)
+  end
 
   defp has_non_empty_custom_field_value?(member, custom_field) do
     case find_cfv(member, custom_field) do

lib/mv_web/live/member_live/index.ex

@@ -1066,13 +1066,6 @@ defmodule MvWeb.MemberLive.Index do
     end
   end
 
-  defp computed_field?(field) do
-    computed_atoms = FieldVisibility.computed_member_fields()
-    computed_strings = Enum.map(computed_atoms, &Atom.to_string/1)
-
-    (is_atom(field) and field in computed_atoms) or
-      (is_binary(field) and field in computed_strings)
-  end
 
   defp apply_sort_to_query(query, field, order) do
     cond do