Yes/no/empty fields

Is there a simple/recommended way to handle fields of the Yes/No/unspecified type - i.e. that would typically map to 1(true)/0(false)/null(empty in the database? Checkbox is the obvious choice which comes up in Studio for boolean values, but I presume that an unchecked box will result in the value being stored as 0 (false), and often the functionality of an application dictates that an unknown value should specifically NOT be mapped to zero/false. The other choice seems to be a dropdown - I assume this maps to an enum field on the database, and I could populate the dropdown with the value/label pairs 0=>No, 1=>Yes, and make sure to uncheck the “required” box, so that the field can be left empty. This seems the only obvious solution, but it just seems clumsy to use an enum when a boolean would be natural. Any advice greatly appreciated.

Looks like it has got to be a dropdown for this purpose, which translates into what you want to see on the web page. The dropdown just needs the name/display pairs 0=>No, 1=>Yes, (blank)=>Unknown/Not applicable/whatever.

A bit more digging reveals that dropdowns do not map to database enums, anyway; they map to varchars. The database does not even know that the value has come via a dropdown list (hence if you import data manually, it will not stop you inserting values not in the dropdown list). Does not seem to be the most elegant mechanism, but for most intents and purposes (php not being fussy about the difference between 0 and ‘0’) I guess it works.

Am on SuiteCRM 7.4.3, by the way, in case anything has changed in subsequent releases.