Examine the data in the PROMO_BEGIN_DATE column of the promotions table: 
You want to display the number of promotions started in 1999 and 2000.
Which query gives the correct output?
A.
Option A
B.
Option B
C.
Option C
D.
Option D
Explanation:
Which query gives the correct output?
Examine the data in the PROMO_BEGIN_DATE column of the promotions table:
You want to display the number of promotions started in 1999 and 2000.
Which query gives the correct output?
why A and why not D?
Not D because SUBSTR(to_char(promo_begin_date,’yyyy’), 8) is NULL
Yep:
TO_CHAR(’04-JAN-00′,’YYYY’,) = 2000 (this conversion gets only the 4 digits year)
and
SUBSTR(‘2000’,8) = NULL (the year from the previous instruction is 4 positions long. Substring starting in th 8th position gets nothing)
Not only that but count(…) is the problem too.
A