<!DOCTYPE html> <html> <head> <meta http-equiv="content-type" content="text/html; charset=UTF-8"> </head> <body text="#000000" bgcolor="#FFFFFF"> Hi, I am looking for idea and design idea regarding persistence of objects. In the DyboApp, the user data are saved in a tree of objects <ul> <li>userData (root)</li> <ul> <li>schools</li> <ul> <li>classGroups</li> <ul> <li>courses</li> <ul> <li>topics</li> <ul> <li>documents</li> </ul> </ul> </ul> </ul> </ul> </ul> The most complex data are the documents. A document represents a metaphor of pages with handwritten notes, and an arbitrary number of tools, dropped pictures from the host filer, etc. Moreover a page may have a model as simple as a background color, or a particular design as horizontal lines, grid, graph paper or a pdf. Because of this complexity, I serialize the documents in individual compressed files, it is fast at saving and loading. Because serializing the userData root save all the data by default, each Document instances in the documents collection (at the bottom of the tree above), are in fact DiskProxy containing the path to the independently serialized Document instances. This works well when saving the whole userData or an individual Document. However, at start-up, accessing the userData load everything, which is fine expect for the documents collection and its Documents instances (through the Disk proxy). As the documents collection, it may become slow when I will have several hundreds of documents. I have some ideas how to improve this, but I am interested to read other opinions and experience on the matter. Thanks <pre class="moz-signature" cols="72">-- <a class="moz-txt-link-freetext" href="http://mamot.fr/@drgeo">http://mamot.fr/@drgeo</a></pre> </body> </html>