Converts specified lowercase string to the uppercase equivalent.
upper(char_expr)
is a character-type column name, variable, or constant expression of char, unichar, varchar, nchar, nvarchar, or univarchar type.
select upper("abcd")
---- ABCD
upper, a string function, converts lowercase to uppercase, returning a character value.
If char_expr or uchar_expr is NULL, upper returns NULL.
Characters that have no upper-ase equivalent are left unmodified.
If a unichar expression is created containing only half of a surrogate pair, an error message appears and the operation is aborted.
ANSI SQL – Compliance level: Transact-SQL extension.
Any user can execute upper.
Documentation Transact-SQL Users Guide
Function lower
