Oracle PL/SQL Programming: A Developer's Workbook

Intermediate

3-10.	Rewrite the following IF statements so that you do not use an IF statement to set the value of no_revenue: DECLARE total_sales NUMBER := sales_for_year (company_id=>1056, yearnum=>1998); no_revenue BOOLEAN; BEGIN IF total_sales <= 0 THEN no_revenue := TRUE; ELSIF total_sales > 0 THEN no_revenue := FALSE; END IF; END;
3-11.	Can you rewrite the following IF statements so that you do not use an IF statement to set the value of no_revenue? DECLARE total_sales NUMBER := sales_for_year (company_id=>1056, yearnum=>1998); no_revenue BOOLEAN; BEGIN IF total_sales <= 0 THEN no_revenue := TRUE; ELSE no_revenue := FALSE; END IF; END;
3-12.	Which procedure is never executed in this IF statement? IF (order_date > SYSDATE) AND order_total >= min_order_total THEN fill_order (order_id, 'HIGH PRIORITY'); ELSIF (order_date < SYSDATE) OR (order_date = SYSDATE) THEN fill_order (order_id, 'LOW PRIORITY'); ELSIF order_date <= SYSDATE AND order_total < min_order_total THEN queue_order_for_addtl_parts (order_id); ELSIF order_total = 0 THEN disp_message (' No items have been placed in this order!'); END IF;
3-13.	What is the difference in logic between these two IF statements? Why do you think it might be advantageous to use the form on the right? IF potholes_after_storm > 1000 THEN mayor_not_reelected; END IF; IF potholes_after_storm > 1000 THEN mayor_not_reelected; ELSE NULL; END IF;
3-14.	Why doesn’t the following code compile? BEGIN IF presidents_lie THEN GOTO big_surprise; ELSIF ceos_don't_care ...