（94）Examine the structure of the PROGRAMS table:

name Null Type

PROG_ID NOT NULL NUMBER(3)

PROG_COST NUMBER(8,2)

START_DATE NOT NULL DATE

END_DATE DATE

Which two SQL statements would execute successfully? (Choose two.)

A. SELECT NVL(ADD_MONTHS(END_DATE, 1), SYSDATE) FROM programs;

B. SELECT TO_DATE(NVL(SYSDATE - END_DATE, SYSDATE)) FROM programs;

C. SELECT NVL(MONTHS_BETWEEN(start_date,end_date),'Ongoing') FROM programs;

D. SELECT NVL(TO_CHAR(MONTHS_BETWEEN(start_date, end_date)),'Ongoing') FROM programs;

答案：（A、D）

解析：

B（X）， NVL(SYSDATE - END_DATE, SYSDATE)这部分没问题，问题出现在TO_DATE函数上

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OCP 1Z0-051-94