public String[] getAliveTags(String[] tagArray){
		LinkedList<String> list = new LinkedList<>();
		
		StringBuffer sqlRequest = new StringBuffer(TAG_IS_ALIVE);
		for(int i = 0; i < tagArray.length -1; i++){
			sqlRequest.append(TAG_IS_ALIVE_CONTINUE);
		}
		
		try {
			PreparedStatement statement = connection.prepareStatement(sqlRequest.toString());
			for(int i = 0; i < tagArray.length; i++){
				statement.setString(i+1, tagArray[i]);				
			}
			ResultSet set = statement.executeQuery();
			
			while(set.next() == true){
				list.add(set.getString("name"));
			}
			
		} catch (SQLException e) {			
			e.printStackTrace();
			return null;
		}
		
		String[] result = new String[list.size()];
		return list.toArray(result);
	}