单项选择题

Which statement is true regarding the COALESCE function?（）

A.It can have a maximum of five expressions in a list
B.It returns the highest NOT NULL value in the list for all rows
C.It requires that all expressions in the list must be of the same data type
D.It requires that at least one of the expressions in the list must have a NOT NULL value

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OCP 11G认证考试

Which statement is true regarding the COALESCE function?（）