Which statement is true regarding the COALESCE function?
A.
It requires that at least one of the expressions in the list must have a NOT NULL value.
B.
It can have a maximum of five expressions in a list.
C.
It returns the highest NOT NULL value in the list for all rows.
D.
It requires that all expressions in the list must be of the same data type.
Check sowmi’s comment:
http://www.aiotestking.com/oracle/which-statement-is-true-regarding-the-coalesce-function/
If all occurrences of expr are numeric datatype or any nonnumeric datatype that can be implicitly converted to a numeric datatype, then Oracle Database determines the argument with the highest numeric precedence, implicitly converts the remaining arguments to that datatype, and returns that datatype.
https://docs.oracle.com/cd/B28359_01/server.111/b28286/functions023.htm#SQLRF00617