Writes the full history for a particular client.

def WriteClientSnapshotHistory(self, clients, cursor=None):
    """Writes the full history for a particular client."""
    client_id = clients[0].client_id
    latest_timestamp = max(client.timestamp for client in clients)

    query = ""
    params = {
        "client_id": db_utils.ClientIDToInt(client_id),
        "latest_timestamp": mysql_utils.RDFDatetimeToTimestamp(latest_timestamp)
    }

    for idx, client in enumerate(clients):
      startup_info = client.startup_info
      client.startup_info = None

      query += """
      INSERT INTO client_snapshot_history (client_id, timestamp,
                                           client_snapshot)
      VALUES (%(client_id)s, FROM_UNIXTIME(%(timestamp_{idx})s),
              %(client_snapshot_{idx})s);

      INSERT INTO client_startup_history (client_id, timestamp,
                                          startup_info)
      VALUES (%(client_id)s, FROM_UNIXTIME(%(timestamp_{idx})s),
              %(startup_info_{idx})s);
      """.format(idx=idx)

      params.update({
          "timestamp_{idx}".format(idx=idx):
              mysql_utils.RDFDatetimeToTimestamp(client.timestamp),
          "client_snapshot_{idx}".format(idx=idx):
              client.SerializeToString(),
          "startup_info_{idx}".format(idx=idx):
              startup_info.SerializeToString(),
      })

      client.startup_info = startup_info

    query += """
    UPDATE clients
       SET last_snapshot_timestamp = FROM_UNIXTIME(%(latest_timestamp)s)
     WHERE client_id = %(client_id)s
       AND (last_snapshot_timestamp IS NULL OR
            last_snapshot_timestamp < FROM_UNIXTIME(%(latest_timestamp)s));

    UPDATE clients
       SET last_startup_timestamp = FROM_UNIXTIME(%(latest_timestamp)s)
     WHERE client_id = %(client_id)s
       AND (last_startup_timestamp IS NULL OR
            last_startup_timestamp < FROM_UNIXTIME(%(latest_timestamp)s));
    """

    try:
      cursor.execute(query, params)
    except MySQLdb.IntegrityError as error:
      raise db.UnknownClientError(client_id, cause=error)