MySQL 8.0

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CREATE TABLE promo_codes  (
  `code` VARCHAR(15),
  `identification` VARCHAR(20),
  `customer_code` VARCHAR(20),
  `status` VARCHAR(9)
);

INSERT INTO promo_codes 
  (`code`, `identification`, `customer_code`, `status`)
VALUES
  ('81Ow3tCs1nNwxKu', '--', '--', 'available'),
  ('I1NdH9F22S7RhU3', '--', '--', 'available'),
  ('Xc942LWe8Z6nt8x', '--', '--', 'available'),
  ('zcLMRO8kSeM7S06', '--', '--', 'available'),
  ('K94erORvzSsU0ik', '--', '--', 'available');
UPDATE promo_codes 
SET 
    identification='12345',
    customer_code='67890',
    status='reserved' 
WHERE status='available' LIMIT 2;
SELECT * FROM promo_codes


code
identification
customer_code
status


81Ow3tCs1nNwxKu
12345
67890
reserved

I1NdH9F22S7RhU3
12345
67890
reserved

Xc942LWe8Z6nt8x
--
--
available

zcLMRO8kSeM7S06
--
--
available

K94erORvzSsU0ik
--
--
available

code	identification	customer_code	status
81Ow3tCs1nNwxKu	12345	67890	reserved
I1NdH9F22S7RhU3	12345	67890	reserved
Xc942LWe8Z6nt8x	--	--	available
zcLMRO8kSeM7S06	--	--	available
K94erORvzSsU0ik	--	--	available