SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c64f5e05f5ff654cbab6ce154996a793f9e464c01aff0287b822032768f3ed99' 
  AND token = 'o9s/DpkmFhgS4jC2ZLE+7X2hNRA3qyM9iyDjuklJOGY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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