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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '03f362783640799288bee3e234ccd306379d60423c619cb3f039893f77924489' 
  AND token = 'FfNhLoQDo5emreL0Ky3PBTHr8NruMFURf1uvsdVdSS8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

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