SQL DataType - How to store a year?

regular 4 byte INT is way too big, is a waste of space!

You don't say what database you're using, so I can't recommend a specific datatype. Everyone is saying "use integer", but most databases store integers as 4 bytes, which is way more than you need. You should use a two byte integer (smallint on SQL Server), which will conserve space.

If you need to store a year in the database, you would either want to use an Integer datatype (if you are dead set on only storing the year) or a DateTime datatype (which would involve storing a date that basically is 1/1/1990 00:00:00 in format).

Just a year, nothing else ? Why not use a simple integer ?

Use integer if all you need to store is the year. You can also use datetime if you think there will be date based calculations while querying this column

I don't think using an integer or any subtype of integer is a good choice. Sooner or later you will have to do other date like operations on it. Also in 2019 let's not worry too much about space. See what those saved 2 bytes costed us in 2000.

I suggest use a date of year + 0101 converted to a true date. Similarly if you need to store a month of a year store year + month + 01 as a true date.

If you have done that you will be able to properly do "date stuff" on it later on

you are trying to insert a year in the database then use:
type YEAR