What's the best practice for fields that hold true/false values?
Such columns can be defined as enum('yes','no') or as tinyint(1). Is one better/faster than the other?
Is it better to use enum('1','0') vs. enum('yes','no') (i.e., does it write 'yes' or 'no' as a string to every row so the database storage size gets bigger)?
Also, ENUM is a non-standard MySql extension. You should avoid it, especially if you can achieve the same results in a standard way.
avoid enum from this reasons
The bottom line is that ENUM has its place, but should be used sparingly. The model should enforce the constraints, not the database; the model should handle interpreting raw data into useful information for your views, not the database.
BOOLEAN type is there for a reason. It is indeed a TINYINT(1) but since it's there, it must be the recommended way.
来源：https://stackoverflow.com/questions/4297149/enumyes-no-vs-tinyint-which-one-to-use