View the Exhibit and examine the structure of the PROMOTIONS table. 
Which SQL statements are valid? (Choose all that apply.)
A.
SELECT promo_id. DECODE(NVL(promo_cost.O).promo_cost * 0.25. 100) “Discount”
FROM promotions;
B.
SELECT promo id. DECODE(promo_cost. 10000.
DECODE(promo_category. ‘Gl\ promo_cost * 25. NULL). NULL) “Catcost” FROM promotions;
C.
SELECT promo_id. DECODE(NULLIF(promo_cost. 10000). NULL. promo_cost*.25, *N/A’)
“Catcost”
FROM promotions;
D.
SELECT promo_id. DECODE(promo_cost. >10000. ‘High’. <10000. ‘Low’) “Range”FROM
promotions;
Explanation:
Note: there are some syntax issues in this question.
Check (same question) http://blog.csdn.net/rlhua/article/details/12869075
How can any of them work with Periods instead of commas?
Please update the options as below:
A. SELECT promo_id, DECODE(NVL(promo_cost,0), promo_cost, promo_cost * 0.25, 100) “Discount”
FROM promotions;
B. SELECT promo_id, DECODE(promo_cost, 10000, DECODE(promo_category, ‘G1’, promo_cost *.25, NULL), NULL) “Catcost”
FROM promotions;
C. SELECT promo_id, DECODE(NULLIF(promo_cost, 10000), NULL, promo_cost*.25, ‘N/A’) “Catcost”
FROM promotions;
D. SELECT promo_id, DECODE(promo_cost, >10000, ‘High’, <10000, 'Low') "Range"
FROM promotions;
There are a lot of syntactical errors in the given question.