4 files changed, 13 insertions, 5 deletions
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb b/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb
index 793f58d4d3..0d7046a705 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb
@@ -299,7 +299,7 @@ module ActiveRecord
       end
 
       def empty_insert_statement_value
-        "VALUES(DEFAULT)"
+        "DEFAULT VALUES"
       end
 
       def case_sensitive_equality_operator
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 1783b036a2..8c83c4f5db 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb
@@ -30,6 +30,10 @@ module ActiveRecord
           super
         end
 
+        def explicit_default?
+          !null && (sql_type =~ /blob/i || type == :text)
+        end
+
         # Must return the relevant concrete adapter
         def adapter
           raise NotImplementedError
@@ -320,6 +324,10 @@ module ActiveRecord
         end
       end
 
+      def empty_insert_statement_value
+        "VALUES ()"
+      end
+
       # SCHEMA STATEMENTS ========================================
 
       def structure_dump #:nodoc:
diff --git a/activerecord/lib/active_record/connection_adapters/column.rb b/activerecord/lib/active_record/connection_adapters/column.rb
index 816b5e17c1..2028abf6f0 100644
--- a/activerecord/lib/active_record/connection_adapters/column.rb
+++ b/activerecord/lib/active_record/connection_adapters/column.rb
@@ -53,6 +53,10 @@ module ActiveRecord
         !default.nil?
       end
 
+      def explicit_default?
+        false
+      end
+
       # Returns the Ruby class that corresponds to the abstract data type.
       def klass
         case type
diff --git a/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb b/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb
index 4a48812807..4d5cb72c67 100644
--- a/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb
@@ -490,10 +490,6 @@ module ActiveRecord
         alter_table(table_name, :rename => {column_name.to_s => new_column_name.to_s})
       end
 
-      def empty_insert_statement_value
-        "VALUES(NULL)"
-      end
-
       protected
         def select(sql, name = nil, binds = []) #:nodoc:
           exec_query(sql, name, binds)