SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '213c15fd13dc93f892c8cbc3810ceea12b285c279e67e602403c7e73ea8bcd98' 
  AND token = 'Oairniu7pY+sdHRXhotxfTTnwFq8huIMnSFkxs2CYQA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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