SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c37f857536d1417032df2987040585102d28c2b4c165e425041b14c3200166ec' 
  AND token = 'kGVwgMatEe0NAqRISZaKDazl23pkfM+VwTSXu7OkWSs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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