YEAR[(2|4)]

A year in two-digit or four-digit format. The default is four-digit
format. YEAR(2) or YEAR(4) differ in display format, but have the same
range of values. In four-digit format, values display as 1901 to 2155,
and 0000. In two-digit format, values display as 70 to 69, representing
years from 1970 to 2069. MySQL displays YEAR values in YYYY or YY
format, but permits assignment of values to YEAR columns using either
strings or numbers.

*Note*: The YEAR(2) data type has certain issues that you should
consider before choosing to use it. As of MySQL 5.6.6, YEAR(2) is
deprecated. YEAR(2) columns in existing tables are treated as before,
but YEAR(2) in new or altered tables are converted to YEAR(4). For more
information, see
http://dev.mysql.com/doc/refman/5.6/en/migrating-to-year4.html.

For additional information about YEAR display format and interpretation
of input values, see http://dev.mysql.com/doc/refman/5.6/en/year.html.

URL: http://dev.mysql.com/doc/refman/5.6/en/date-and-time-type-overview.html

