SQL Server 2019

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CREATE TABLE dbo.Customers
(
    CustomerID varchar(50) NULL,
    Cust_Name  varchar(50) NULL,
    Address    varchar(50) NULL
);

CREATE TABLE dbo.Items
(
    ItemID   varchar(50) NULL,
    ItemName varchar(50) NULL,
    Price    decimal(18, 2) NULL
);

CREATE TABLE dbo.Orders
(
    OrderID    varchar(50) NULL,
    OrderDate  date NULL,
    ItemID     varchar(50) NULL,
    CustomerID varchar(50) NULL
);

CREATE INDEX ix_Customers ON Customers(CustomerID, Cust_Name);
CREATE INDEX ix_Items ON Items(ItemID, ItemName);
CREATE INDEX ix_Orders ON Orders(CustomerID, OrderId);

INSERT dbo.Customers (CustomerID, Cust_Name, Address) VALUES 
(N'Cust-1', N'Badang', N'Makati'),
(N'Cust-2', N'Hanzo', N'Taguig'),
(N'Cust-3', N'Lilia', N'Rizal'),
(N'Cust-4', N'Layla', N'Laguna'),
(N'Cust-5', N'Lesley', N'Laguna'),
(N'Cust-6', N'Balmond', N'Makati'),
(N'Cust-7', N'Chou', N'Navotas'),
(N'Cust-8', N'Eudora', N'Malabon'),
(N'Cust-9', N'Miya', N'Taguig'),
(N'Cust-10', N'Cecilion', N'Navotas'),
(N'Cust-11', N'Roger', N'Baguio'),
(N'Cust-12', N'Cong', N'Cebu'),
(N'Cust-13', N'Emman', N'Cebu'),
(N'Cust-14', N'Jerome', N'Baguio'),
(N'Cust-15', N'Gusion', N'Davao'),
(N'Cust-16', N'Lancelot', N'Iloilo'),
(N'Cust-17', N'Granger', N'Antipolo'),
(N'Cust-18', N'Irithel', N'Makati'),
(N'Cust-19', N'Alucard', N'Binondo'),
(N'Cust-20', N'Carmilla', N'Malabon');

INSERT dbo.Items (ItemID, ItemName, Price) VALUES 
(N'IT-1', N'Samsung S9', CAST(32000.00 AS Decimal(18, 2))),
(N'IT-2', N'Samsung S10', CAST(40000.00 AS Decimal(18, 2))),
(N'IT-3', N'Huawei P30', CAST(29000.00 AS Decimal(18, 2))),
(N'IT-4', N'Huawei Mate30', CAST(31000.00 AS Decimal(18, 2))),
(N'IT-5', N'Realme 6', CAST(9999.99 AS Decimal(18, 2))),
(N'IT-6', N'Realme 6 Pro', CAST(11000.00 AS Decimal(18, 2))),
(N'IT-7', N'Xiaomi Note 9', CAST(8000.00 AS Decimal(18, 2))),
(N'IT-8', N'Xiaomi Note 10', CAST(11000.00 AS Decimal(18, 2))),
(N'IT-9', N'LG V40', CAST(15000.00 AS Decimal(18, 2))),
(N'IT-10', N'LG V50', CAST(23000.00 AS Decimal(18, 2)));

INSERT dbo.Orders (OrderID, OrderDate, ItemID, CustomerID) VALUES 
(N'OR-1', CAST(N'2019-08-14' AS Date), N'IT-6', N'Cust-10'),
(N'OR-2', CAST(N'2019-12-04' AS Date), N'IT-3', N'Cust-9'),
(N'OR-3', CAST(N'2017-08-20' AS Date), N'IT-7', N'Cust-13'),
(N'OR-4', CAST(N'2018-06-12' AS Date), N'IT-10', N'Cust-7'),
(N'OR-5', CAST(N'2017-02-28' AS Date), N'IT-5', N'Cust-6'),
(N'OR-6', CAST(N'2019-05-21' AS Date), N'IT-9', N'Cust-11'),
(N'OR-7', CAST(N'2017-12-27' AS Date), N'IT-2', N'Cust-5'),
(N'OR-8', CAST(N'2017-02-10' AS Date), N'IT-4', N'Cust-3'),
(N'OR-9', CAST(N'2018-09-12' AS Date), N'IT-10', N'Cust-9'),
(N'OR-10', CAST(N'2018-01-17' AS Date), N'IT-3', N'Cust-4'),
(N'OR-11', CAST(N'2019-02-11' AS Date), N'IT-6', N'Cust-7'),
(N'OR-12', CAST(N'2018-02-23' AS Date), N'IT-4', N'Cust-9'),
(N'OR-13', CAST(N'2018-11-01' AS Date), N'IT-7', N'Cust-2'),
(N'OR-14', CAST(N'2018-01-11' AS Date), N'IT-8', N'Cust-4'),
(N'OR-15', CAST(N'2018-05-28' AS Date), N'IT-1', N'Cust-2'),
(N'OR-16', CAST(N'2017-01-03' AS Date), N'IT-6', N'Cust-1'),
(N'OR-17', CAST(N'2019-01-17' AS Date), N'IT-8', N'Cust-9'),
(N'OR-18', CAST(N'2017-06-22' AS Date), N'IT-3', N'Cust-7'),
(N'OR-19', CAST(N'2017-04-09' AS Date), N'IT-7', N'Cust-3'),
(N'OR-20', CAST(N'2019-09-15' AS Date), N'IT-5', N'Cust-5'),
(N'OR-21', CAST(N'2017-08-13' AS Date), N'IT-9', N'Cust-4');

51 rows affected

Cust_Name	ItemName	Price
Miya	Huawei P30	29000.00
Chou	LG V50	23000.00
Roger	LG V40	15000.00
Lesley	Samsung S10	40000.00
Lilia	Huawei Mate30	31000.00
Miya	LG V50	23000.00
Layla	Huawei P30	29000.00
Miya	Huawei Mate30	31000.00
Hanzo	Samsung S9	32000.00
Chou	Huawei P30	29000.00
Layla	LG V40	15000.00

Warning: Null value is eliminated by an aggregate or other SET operation.