SQL Server 2022

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CREATE TABLE YourTable (
  "Main_Key" INTEGER,
  "IDx" INTEGER,
  "IDy" INTEGER,
  "IDz" INTEGER,
  "Count" INTEGER,
  INDEX IX CLUSTERED (Main_key, IDx, IDy)
);

INSERT INTO YourTable
  ("Main_Key", "IDx", "IDy", "IDz", "Count")
VALUES
  ('123450', '0', '0', '0', '0'),
  ('123450', '0', '0', '1', '1'),
  ('123450', '0', '0', '2', '0'),
  ('123450', '0', '0', '3', '5'),
  ('123450', '1', '0', '0', '4'),
  ('123450', '1', '0', '1', '3'),
  ('123450', '1', '0', '2', '8'),
  ('123450', '1', '0', '3', '0'),
  ('123450', '0', '1', '0', '5'),
  ('123450', '0', '1', '1', '6'),
  ('123450', '0', '1', '2', '0'),
  ('123450', '0', '1', '3', '0'),
  ('123450', '1', '1', '0', '6'),
  ('123450', '1', '1', '1', '2'),
  ('123450', '1', '1', '2', '3'),
  ('123450', '1', '1', '3', '1'),
  ('123450', '0', '2', '0', '4'),
  ('123450', '0', '2', '1', '5'),
  ('123450', '0', '2', '2', '0'),
  ('123450', '0', '2', '3', '7'),
  ('123450', '1', '2', '0', '9'),
  ('123450', '1', '2', '1', '9'),
  ('123450', '1', '2', '2', '2'),
  ('123450', '1', '2', '3', '5');

24 rows affected

main_key	IDx	IDy	(No column name)
123450	0	0	6
123450	0	1	11
123450	0	2	16
123450	1	0	15
123450	1	1	12
123450	1	2	25