OCP-1Z0-051-V9 02-88題
阿新 • • 發佈：2018-12-22
88. You need to calculate the number of days from 1st January 2007 till date.
Dates are stored in the default format of dd-mon-rr.
Which SQL statements would give the required output? (Choose two .)
A. SELECT SYSDATE - '01-JAN-2007' FROM DUAL;
B. SELECT SYSDATE - TO_DATE('01/JANUARY/2007') FROM DUAL;
C. SELECT SYSDATE - TO_DATE('01-JANUARY-2007') FROM DUAL;
D. SELECT TO_CHAR(SYSDATE, 'DD-MON-YYYY') - '01-JAN-2007' FROM DUAL;
E. SELECT TO_DATE(SYSDATE, 'DD/MONTH/YYYY') - '01/JANUARY/2007' FROM DUAL;
Answer: BC 答案解析：日期與字串做表示式計算，隱式將日期轉換為字串，而字串之間不能相減，所以ADE都是字元之間相減，所以錯誤。BC之間相減是日期與日期之間的減，得出數字，是正確的。