Merge pull request rails#51325 from gabriel-amaral/old-upsert-for-on-duplicate-raw-sql

Do not try to alias on key update when raw SQL is supplied

Author: byroot

activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb

@@ -650,10 +650,10 @@ def build_insert_sql(insert) # :nodoc:
           if insert.skip_duplicates?
             sql << " ON DUPLICATE KEY UPDATE #{no_op_column}=#{values_alias}.#{no_op_column}"
           elsif insert.update_duplicates?
-            sql << " ON DUPLICATE KEY UPDATE "
             if insert.raw_update_sql?
-              sql << insert.raw_update_sql
+              sql = +"INSERT #{insert.into} #{insert.values_list} ON DUPLICATE KEY UPDATE #{insert.raw_update_sql}"
             else
+              sql << " ON DUPLICATE KEY UPDATE "
               sql << insert.touch_model_timestamps_unless { |column| "#{insert.model.quoted_table_name}.#{column}<=>#{values_alias}.#{column}" }
               sql << insert.updatable_columns.map { |column| "#{column}=#{values_alias}.#{column}" }.join(",")
             end

activerecord/test/cases/insert_all_test.rb

@@ -768,6 +768,26 @@ def test_upsert_all_updates_using_provided_sql
     assert_equal "written", Book.find(2).status
   end
 
+  if current_adapter?(:Mysql2Adapter) || current_adapter?(:TrilogyAdapter)
+    def test_upsert_all_updates_using_values_function_on_duplicate_raw_sql
+      skip unless supports_insert_on_duplicate_update?
+
+      b1 = Book.create!(name: "Name")
+      b2 = Book.create!(name: nil)
+
+      Book.upsert_all(
+        [{ id: b1.id, name: "No Name" }, { id: b2.id, name: "No Name" }],
+        on_duplicate: Arel.sql("name = IFNULL(name, values(name))")
+      )
+
+      b1.reload
+      b2.reload
+
+      assert_equal "Name", b1.name
+      assert_equal "No Name", b2.name
+    end
+  end
+
   def test_upsert_all_updates_using_provided_sql_and_unique_by
     skip unless supports_insert_on_duplicate_update? && supports_insert_conflict_target?