Changes between Version 94 and Version 95 of HaitiGISToDo

Timestamp:

02/04/10 03:18:01 (13 years ago)

Author:

Fran Boon

Comment:

--

HaitiGISToDo

@@ -6 +6 @@
 
 dokotreas & runneals joined the team
-
-RT: haiti-dev.sahanafoundation.org and haiti-test.sahanafoundation.org
 
 === Bugs ===
  * #87
+
 === Documentation ===
 The focus should be on concepts & Helpfile tweaks rather than detailed UI paths, as the UI is not final.
@@ -115 +114 @@
 }}}
 === Code Cleanup ===
- * Move GIS functions to a new {{{modules/s3gis.py}}}
- * DRY the gis_config parsing in {{{controlers/gis.py}}} (currently in 3 different places!)
+ * ~~Move GIS functions to a new {{{modules/s3gis.py}}}~~
+ * DRY the gis_config parsing in {{{controllers/gis.py}}} (currently in 3 different places!)
   * pass a single s3.gis var through to views
+
+=== Hierarchical Trees ===
+We currently use a simple Adjacency List model for gis_location (i.e. a single 'parent' field).
+
+This is fast for writes, but slow for reads, which is not the ideal optimisation for our use case.
+
+We should move to one of these models:
+ * Materialised Path: http://docs.tabo.pe/django-treebeard/tip/#module-treebeard.mp_tree
+ * Nested Sets: http://docs.tabo.pe/django-treebeard/tip/#module-treebeard.ns_tree
+ * Modified Preorder Tree Traversal:
+  * http://articles.sitepoint.com/print/hierarchical-data-database
+  * http://www.web2pyslices.com/main/slices/take_slice/27
+ * http://groups.google.com/group/web2py/browse_thread/thread/d1e1ca4eb75174ac
 
 === IS_LOCATION Validator ===