Here is the approach I would probably take unless you have many hundreds of child tasks.
I would keep a list of keys of all children of each project/task. (You can then do a db.get and get all immediate children with single call) and each child has a reference to it's parent. In addition in each item keep a list of all parents keys back to the root. That way you can search for all children in part of the tree/subtree (This approach is especially useful if you have multiple child types) as back ref sets are kind specific. Keep a running count of complete children at each level, rather than trying to calculate the current state in a single big function, (keep these subsidiary values up to date through tasks) T On Apr 18, 8:29 pm, gops <patelgo...@gmail.com> wrote: > hi , i am designing a simple project based to do list. the idea is to > define tasks under project ( no workflow - just "task is completed" or > not is required. ) in a hirarchial way. i.e. each task has multiple > task and that task may have other multiple task. a project can be said > to be completed if all task under that project are completed. , i > tought of using refrenceproeperty to create hirarchy , but could not > figure out easy way ( which do not take more than 30 seconds to find > all the children of a project and check weather it is completed or > not ) . to detect if project is complete or not. how to design > database for such job ? and also , if i need to copy the project in > order to define another project , how to copy hierarchical data ? > > -- > You received this message because you are subscribed to the Google Groups > "Google App Engine" group. > To post to this group, send email to google-appeng...@googlegroups.com. > To unsubscribe from this group, send email to > google-appengine+unsubscr...@googlegroups.com. > For more options, visit this group > athttp://groups.google.com/group/google-appengine?hl=en. -- You received this message because you are subscribed to the Google Groups "Google App Engine" group. To post to this group, send email to google-appeng...@googlegroups.com. To unsubscribe from this group, send email to google-appengine+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine?hl=en.
