SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '89988e49c0274340ee69cee8fcaf57d35e652de05c890d9b6621dbc07ac6b85a' 
  AND token = 'L3MQanjSO0MwWXk5/Y30N9+xmx+ud4ZbN0z8FX648o8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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