SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a8c56e39ffd88e3188b9c566e219394f111476257771ae7de205c170e2550c93' 
  AND token = 'FFb6AdQdEnxtaKcdZotUToSVdopbo8KK84hanodo7bw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}