Fix insert_all to not update existing records

Author: fatkodima

activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb

@@ -628,24 +628,26 @@ def default_index_type?(index) # :nodoc:
       end
 
       def build_insert_sql(insert) # :nodoc:
+        # Can use any column as it will be assigned to itself.
         no_op_column = quote_column_name(insert.keys.first) if insert.keys.first
 
         # MySQL 8.0.19 replaces `VALUES(<expression>)` clauses with row and column alias names, see https://dev.mysql.com/worklog/task/?id=6312 .
         # then MySQL 8.0.20 deprecates the `VALUES(<expression>)` see https://dev.mysql.com/worklog/task/?id=13325 .
         if supports_insert_raw_alias_syntax?
+          quoted_table_name = insert.model.quoted_table_name
           values_alias = quote_table_name("#{insert.model.table_name.parameterize}_values")
           sql = +"INSERT #{insert.into} #{insert.values_list} AS #{values_alias}"
 
           if insert.skip_duplicates?
             if no_op_column
-              sql << " ON DUPLICATE KEY UPDATE #{no_op_column}=#{values_alias}.#{no_op_column}"
+              sql << " ON DUPLICATE KEY UPDATE #{no_op_column}=#{quoted_table_name}.#{no_op_column}"
             end
           elsif insert.update_duplicates?
             if 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.touch_model_timestamps_unless { |column| "#{quoted_table_name}.#{column}<=>#{values_alias}.#{column}" }
               sql << insert.updatable_columns.map { |column| "#{column}=#{values_alias}.#{column}" }.join(",")
             end
           end

activerecord/test/cases/insert_all_test.rb

@@ -188,10 +188,10 @@ def test_insert_all_with_skip_duplicates_and_autonumber_id_given
   def test_skip_duplicates_strategy_does_not_secretly_upsert
     skip unless supports_insert_on_duplicate_skip?
 
-    book = Book.create!(author_id: 8, name: "Refactoring", format: "EXPECTED")
+    book = Book.create!(format: "EXPECTED", author_id: 8, name: "Refactoring")
 
     assert_no_difference "Book.count" do
-      Book.insert({ author_id: 8, name: "Refactoring", format: "UNEXPECTED" })
+      Book.insert_all([{ format: "UNEXPECTED", author_id: 8, name: "Refactoring" }])
     end
 
     assert_equal "EXPECTED", book.reload.format