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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5d8ff986a23cdf8bbd5c7408ece282d0c6cf063d3ffcf55dca7295885e1e4ab6' 
  AND token = 'LQip+1plHrFDtQ6OlFkDRhNpvM62BTiaMeVrJBW4MgY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

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