What is the best way to store a birthday in MySQL?

Question

MySQL

It is necessary to make it possible to indicate in the questionnaire separately the year of birth, separately the day of birth (day + month), and with the possibility of not specifying one of the parameters, as well as with a search by range, for example, from October 3 to November 13. What is the best way to keep a birthday? If DATE, then an unnecessary year will be stored there, and it must be selected as a leap year so that February 29 is recorded. And it's hard to compare values.

Answer 1

Birthday (year, month, day) is better stored in DATE, obviously. Do not break them into columns, but operate on the data inside the database.

Answer 2

UNIX TIMESTAMP as an option.

Answer 3

store it as char(8) YYYYMMDD
for missing data set to 0, if data is complete then run checks. Such dates can also be stored separately in DATE