PHPMaker v2019.0.4 does not support MySQL BIT fields. Support for it would be great.
A bit field is a value with a number range defined by the data model owner (base 2 range of single bit to BIGINT). It is treated via SQL as an UNSIGNED integer value, so it it transparent to the application. Application does not know (and does not need to know) if value "1" is stored in BIT(1), BIT(13), TINYINT, BIGINT or ENUM(0,1) when using SQL.