Oracle PL/SQL Programming, Third Edition

Name

UPPER

Synopsis

The UPPER function converts all letters in the specified string to uppercase. UPPER (and LOWER) is an overloaded function, and will return a fixed-length string if the incoming string is fixed-length. The specifications for the UPPER function are:

FUNCTION UPPER (string1 IN CHAR) RETURN CHAR
FUNCTION UPPER (string1 IN VARCHAR2) RETURN VARCHAR2

UPPER will not change any characters in the string that are not letters, as case is irrelevant for numbers and special characters such as the dollar sign.

Here are some examples of the effect of UPPER:

UPPER ('Munising MI 49862') --> 'MUNISING MI 49862'
UPPER ('Jenny') --> 'JENNY'

The UPPER and LOWER functions are useful for guaranteeing a consistent case when comparing strings.