MySQL 5.7

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CREATE TABLE Product(
ProductID integer PRIMARY KEY,
ProductName text,
ProductFinish text,
ProductStandardPrice integer,
ProductLineId integer);
INSERT INTO Product VALUES(1,'End Table', 'Cherry', 175, 1);
INSERT INTO Product VALUES(2,'Coffee Table', 'Natural Ash', 200, 2);
INSERT INTO Product VALUES(3,'Computer Desk', 'Natural Ash', 375, 2);
INSERT INTO Product VALUES(4,'Entertainment Center', 'Natural Maple', 650, 3);
INSERT INTO Product VALUES(5,'Writers Desk', 'Cherry', 325, 1);
INSERT INTO Product VALUES(6,'8-Drawer Desk', 'White Ash', 750, 2);
INSERT INTO Product VALUES(7,'Dining Table', 'Natural Ash', 800, 2);
INSERT INTO Product VALUES(8,'Computer Desk', 'Walnut', 250, 3);
CREATE PROCEDURE ProductLineSale ()
BEGIN
  SELECT *,
         CASE WHEN ProductStandardPrice >= 400 THEN (ProductStandardPrice * 0.9)
              ELSE (ProductStandardPrice * 0.85)
         END AS SalePrice
  FROM Product;
END
CALL ProductLineSale()


ProductID
ProductName
ProductFinish
ProductStandardPrice
ProductLineId
SalePrice


1
End Table
Cherry
175
1
148.75

2
Coffee Table
Natural Ash
200
2
170.00

3
Computer Desk
Natural Ash
375
2
318.75

4
Entertainment Center
Natural Maple
650
3
585.0

5
Writers Desk
Cherry
325
1
276.25

6
8-Drawer Desk
White Ash
750
2
675.0

7
Dining Table
Natural Ash
800
2
720.0

8
Computer Desk
Walnut
250
3
212.50

ProductID	ProductName	ProductFinish	ProductStandardPrice	ProductLineId	SalePrice
1	End Table	Cherry	175	1	148.75
2	Coffee Table	Natural Ash	200	2	170.00
3	Computer Desk	Natural Ash	375	2	318.75
4	Entertainment Center	Natural Maple	650	3	585.0
5	Writers Desk	Cherry	325	1	276.25
6	8-Drawer Desk	White Ash	750	2	675.0
7	Dining Table	Natural Ash	800	2	720.0
8	Computer Desk	Walnut	250	3	212.50