Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7a7aea26f80cc87f64dfdfc983098e65bbad1fa97a0a40d978502e5831de1e26' 
  AND token = 'h/HlXK+oCAzC32lV6ePMyCkWAeLnAYHXDEGZh8gG920=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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