SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '480e13cf84673c6dfd2142e43031fb6c688695f43a1502cca8a57e74c9c8637a' 
  AND token = 'Iq/TCeOyBc35WO0S4AcHzl8efYnL/Y4eZhZUSoULkw0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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