Default case specificity varies with mode.
Case specificity does not apply to CLOB types.
CHARACTER and VARCHAR data columns defined in ANSI mode are defined as CASESPECIFIC by default. This means that the values 'aa' and 'AA' are not treated as equals.
An option of NOT CASESPECIFIC is implemented to allow columns to be not case specific. NOT CASESPECIFIC is a Teradata extension to the ANSI standard.
CHARACTER and VARCHAR data columns defined in Teradata mode (with the exception of character data defined as CHAR or VARCHAR CHARACTER SET GRAPHIC) are defined as NOT CASESPECIFIC by default.
Because Latin characters have canonical representation in all Teradata Database character sets, the effect of the UPPERCASE function is the same for each character set (with the exception of KANJI1, where multibyte characters are not converted to uppercase).