SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '97ff98cf63f3d660f1d32cf3c44aa9d32c46884b142d81317e2a2e7bab62e6e7' 
  AND token = 'vEFKozTte4Rd4EjUZKYYr5d62rwhmnGBwWStnqjnYS4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}