SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '801ad2b28726c5e41f95cfe708068a89c20e08427df67390357540ad699257bf' 
  AND token = 'Nu1h2nsX62+7XfKUTR/+KyCfbXBCvIxUpPt/qa7Mh4U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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