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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd7873d5c21f0d0f1cb439e7394909de441fca773bed40b93fa8b683b09c2a2ae' 
  AND token = 'keWXmkwnBd6t3APw4fCSNL2nsOQ1z5bdSorjt6DPWN4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

Explain
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE								Impossible WHERE noticed after reading const tables