Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b0d30227e146af1e408c2418ebaadf18a7b0f8f81d81ab5fe0d6e94a5b540622' 
  AND token = 'ZM+rQFvBKhQL2vFisAJEE2+OLhXOEX/kY0xk/FPQmMA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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