SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c760a7777e7bc009cc091513394294b61cdad54a53bf4cf508bcb6f80db2b353' 
  AND token = 'Cwm76O8gWyOdSESMb/gg2NKgQ/zFZzaGw+T3BnW+V+M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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