1 files changed, 13 insertions, 5 deletions
diff --git a/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb b/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb
index d40f38fb77..13c799b64a 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb
@@ -54,10 +54,6 @@ module ActiveRecord
         super(connection, logger, config)
 
         @statements = StatementPool.new(self.class.type_cast_config_to_integer(config[:statement_limit]))
-
-        if version < "5.5.8"
-          raise "Your version of MySQL (#{version_string}) is too old. Active Record supports MySQL >= 5.5.8."
-        end
       end
 
       def version #:nodoc:
@@ -76,6 +72,10 @@ module ActiveRecord
         !mariadb? && version >= "8.0.1"
       end
 
+      def supports_expression_index?
+        !mariadb? && version >= "8.0.13"
+      end
+
       def supports_transaction_isolation?
         true
       end
@@ -535,6 +535,12 @@ module ActiveRecord
       end
 
       private
+        def check_version
+          if version < "5.5.8"
+            raise "Your version of MySQL (#{version_string}) is too old. Active Record supports MySQL >= 5.5.8."
+          end
+        end
+
         def combine_multi_statements(total_sql)
           total_sql.each_with_object([]) do |sql, total_sql_chunks|
             previous_packet = total_sql_chunks.last
@@ -622,6 +628,8 @@ module ActiveRecord
         # See https://dev.mysql.com/doc/refman/5.7/en/error-messages-server.html
         ER_DUP_ENTRY            = 1062
         ER_NOT_NULL_VIOLATION   = 1048
+        ER_NO_REFERENCED_ROW    = 1216
+        ER_ROW_IS_REFERENCED    = 1217
         ER_DO_NOT_HAVE_DEFAULT  = 1364
         ER_ROW_IS_REFERENCED_2  = 1451
         ER_NO_REFERENCED_ROW_2  = 1452
@@ -638,7 +646,7 @@ module ActiveRecord
           case error_number(exception)
           when ER_DUP_ENTRY
             RecordNotUnique.new(message)
-          when ER_ROW_IS_REFERENCED_2, ER_NO_REFERENCED_ROW_2
+          when ER_NO_REFERENCED_ROW, ER_ROW_IS_REFERENCED, ER_ROW_IS_REFERENCED_2, ER_NO_REFERENCED_ROW_2
             InvalidForeignKey.new(message)
           when ER_CANNOT_ADD_FOREIGN
             mismatched_foreign_key(message)