Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '75b487b5c0055a250954cfd46c2cba5ec6cd90e3b0fc74dd91cf39c5d0ef8f3d' 
  AND token = 'g0rxL8cTShQ2tq/I46TPiqzEPbsMh9Z9g8UWS8G7urs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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