[Modeling-cvs] ProjectModeling/Modeling CustomObject.py,1.16,1.17

[<sbi...@us...>]

Update of /cvsroot/modeling/ProjectModeling/Modeling
In directory sc8-pr-cvs1:/tmp/cvs-serv6026

Modified Files:
	CustomObject.py 
Log Message:
Added full documentation for snapshot_raw(), including the special case where a fk value can get out-of-sync

Index: CustomObject.py
===================================================================
RCS file: /cvsroot/modeling/ProjectModeling/Modeling/CustomObject.py,v
retrieving revision 1.16
retrieving revision 1.17
diff -C2 -d -r1.16 -r1.17
*** CustomObject.py	28 Jul 2003 06:20:19 -0000	1.16
--- CustomObject.py	29 Jul 2003 18:42:13 -0000	1.17
***************
*** 296,299 ****
--- 296,331 ----
      keys are allAttributesKeys() with their corresponding values.
  
+     Special care should be taken when examining the values for primary keys
+     and foreign keys:
+ 
+       - if your object and all its related objects are already saved in the
+         database, you'll get the PK's and FKs' values, as expected (a special
+         case exists where a FK value can get out-of-sync, see below)
+ 
+       - if your object is inserted in an EditingContext but has not been saved
+         yet, the PK value will be its TemporaryGlobalID, since there is no way
+         to know the value it will get when it is saved,
+ 
+       - if your object has a to-one relationship to an other object that is
+         inserted in an EditingContext but not saved yet, the FK's value will
+         be that related object's TemporaryGlobalID --for the same reason then
+         above.
+ 
+       - Last, if the object's entity defines a foreign key involved in a
+         to-many relationship pointing to it but with no inverse (i.e. self's
+         entity has no to-one relationship using this foreign key), the
+         returned value will its value stored in the Database's cache managed
+         by the framework. In other words, this value will be exact after each
+         saveChanges(), and the first time the object is fetched; afterwards,
+         if the object on the other side modifies its relation pointing to
+         'self' (e.g. removes it), the value will be out-of-sync with the
+         object graph and will remain as-is until the EditingContext saves its
+         changes again.
+ 
+     Note: this method does not care about PKs or FKs being marked as class
+     properties. Even when they are class properties, it does NOT look at their
+     values, instead the returned values are extracted by examining the objects
+     related to 'self'.
+       
      Raises ObjectNotRegisteredError if the object itself is not registered in
        an EditingContext, or if any of the objects it is in relation w/ is not