def add_column(table_name, column_name, type, options = {})
if option_not_null = options[:null] == false
option_not_null = options.delete(:null)
end
add_column_sql = "ALTER TABLE #{quote_table_name(table_name)} ADD #{quote_column_name(column_name)} #{type_to_sql(type, options[:limit], options[:precision], options[:scale])}"
add_column_options!(add_column_sql, options)
execute(add_column_sql)
if option_not_null
alter_column_sql = "ALTER TABLE #{quote_table_name(table_name)} ALTER #{quote_column_name(column_name)} NOT NULL"
end
end