SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'de2372541efde539a2b7490deab800d04e56a8186938ba59a22520d559146d5f' 
  AND token = 'JXuZuc4h99U/l4Pn9PU4BzAYS1rq4Px/1KG/fPocYSQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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