4. Which two statements are true regarding single row functions? (Choose two.)
A. They accept only a single argument.
B. They can be nested only to two levels.
C. Arguments can only be column values or constants.
D. They always return a single result row for every row of a queried table.
E. They can return a data type value different from the one that is referenced.

答案: DE
考點：單行函式

A.單行函式只能接收一個引數，錯誤，單行函式可以接收一個或多個引數
B.單行函式最多巢狀兩層，錯誤，單行函式可以巢狀多層，多行函式最多巢狀兩層
C.引數只能是列值或者常量，錯誤，引數也可以是變數或者表示式
D.對於查詢表中的每一行，單行函式返回一行結果，正確
E.函式返回結果的資料型別可以和引用的資料型別不同，正確

【OCP】Oracle 11g OCP 1Z0-051 004

相關文章