DOUBLE PRECISION[(M,D)] [UNSIGNED] [ZEROFILL], REAL[(M,D)] [UNSIGNED]
[ZEROFILL]

These types are synonyms for DOUBLE. Exception: If the REAL_AS_FLOAT
SQL mode is enabled, REAL is a synonym for FLOAT rather than DOUBLE.

URL: http://dev.mysql.com/doc/refman/5.1/en/numeric-type-overview.html

