improvement: set prefer_transaction? to false in generated repos

lib/igniter.ex

@@ -12,6 +12,12 @@ defmodule AshPostgres.Igniter do
       %Version{major: #{min_pg_version.major}, minor: #{min_pg_version.minor}, patch: #{min_pg_version.patch}}
     end
 
+    # Don't open unnecessary transactions
+    # will default to `false` in 4.0
+    def prefer_transaction? do
+      false
+    end
+
     def installed_extensions do
       # Add extensions here, and the migration generator will install them.
       ["ash-functions"]

lib/mix/tasks/ash_postgres.install.ex

@@ -368,6 +368,10 @@ defmodule Mix.Tasks.AshPostgres.Install do
       repo,
       &configure_installed_extensions_function/1
     )
+    |> Igniter.Project.Module.find_and_update_module!(
+      repo,
+      &configure_prefer_transaction_function/1
+    )
     |> Igniter.Project.Module.find_and_update_module!(
       repo,
       &configure_min_pg_version_function(&1, repo, opts)
@@ -443,6 +447,23 @@ defmodule Mix.Tasks.AshPostgres.Install do
     end
   end
 
+  defp configure_prefer_transaction_function(zipper) do
+    case Igniter.Code.Function.move_to_def(zipper, :prefer_transaction?, 0) do
+      {:ok, zipper} ->
+        {:ok, zipper}
+
+      _ ->
+        {:ok,
+         Igniter.Code.Common.add_code(zipper, """
+         # Don't open unnecessary transactions
+         # will default to `false` in 4.0
+         def prefer_transaction? do
+           false
+         end
+         """)}
+    end
+  end
+
   defp configure_min_pg_version_function(zipper, repo, opts) do
     case Igniter.Code.Function.move_to_def(zipper, :min_pg_version, 0) do
       {:ok, zipper} ->