SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '8a7affef077d5d08ceb11c57793301114952a06fe84e7c997a17235b5fcd60e1' 
  AND token = 'rv5vW0OCYU+fJen2lzXXlMPx/esBa2RzGDap8EP5snU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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