GREATEST()
GREATEST(value,value, ...)
This function compares two or more values, returning the
greatest value. In an INTEGER data type context,
all values are treated as integers for comparison. In a
REAL data type context, all values are treated as
REAL values for comparison. If any parameter
contains a case-sensitive string
(i.e., with a BINARY keyword), all values are
compared as case-sensitive strings. Here is an example:
SELECT GREATEST(col1, col2, col3);