ucase returns a copy of string str with all the lowercase alphabetical characters converted to corresponding uppercase letters. This includes also the diacritic letters present in the ISO 8859/1 standard in range 224 - 254 decimal, excluding the character 255, y diaeresis, which is not converted to a German double-s.
upper is just an alias for ucase.
ucase('AbracadabrA') -> 'ABRACADABRA'