Type:
Class
ActiveRecord::Migration::CommandRecorder
records commands done
during a migration and knows how to reverse those commands. The CommandRecorder knows how to invert the
following commands:
-
add_column
-
add_index
-
add_timestamps
-
create_table
-
create_join_table
-
remove_timestamps
-
rename_column
-
rename_index
-
rename_table