Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9c5f786e5a8287c873e518c03b7e7b6594f896ad6389e6563d1cdb32e920dcb6' 
  AND token = 'QZg9aUmO8ZU3SDjQxRrar6kmHJGXngY75HbxOAIM/K4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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