SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cf776a6248529054ffed131b1b6e7ed947049a72272f1b2384b9a5f24689c95a' 
  AND token = '9bGym1CFVSGcaElHAHkIUTQYMy2LnNoeVsbq44TaWgE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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