def internal_types
types = super
types['tinyint'] = Integer
types['tinyint unsigned'] = Integer
types['smallint unsigned'] = Integer
types['mediumint'] = Integer
types['mediumint unsigned'] = Integer
types['int unsigned'] = Integer
types['bigint'] = Integer
types['bigint unsigned'] = Integer
types['double'] = Float
types['decimal'] = String
types['datetime'] = Timestamp
types['year'] = Date
types['tinyblob'] = String
types['tinytext'] = String
types['blob'] = String
types['text'] = String
types['mediumblob'] = String
types['mediumtext'] = String
types['longblob'] = String
types['longtext'] = String
types
end