You appear to be asking about date/time "column types" (in DBA terms) for MySQL, and I assume you wish to work with such values conveniently in Perl.

I'm an OOP fan, so I'd suggest Time::Piece::MySQL . It lets you work with intervals of time, and dissect any date-time you'd like; and it reads and writes exactly what MySQL expects for its 'timestamp', 'datetime' and 'date' column types. And you can easily do addition/subtraction of intervals expressed as seconds, and compare times easily; '+', '-', '<' and so on can be overloaded for you. All that comes from the general interface of Time::Piece .

Happy coding!