You can't. Empty properties are the equivalent of unindexed properties. You'll need to iterate over all the Entities in your datastore and update them. The Mapper API is a very good tool for this:
http://code.google.com/p/appengine-mapreduce/ On Mon, Sep 13, 2010 at 12:20 PM, Benjamin <bsaut...@gmail.com> wrote: > Brain freeze guys - > > I added a property to my object and persisted in the datastore. The > older object have now have a column that when viewed in the control > panel have a value of <missing>. I need to query those objects so i > can update them - propname == null , propname == "" - I can't seem > to find the right syntax for this. > > -- > You received this message because you are subscribed to the Google Groups > "Google App Engine for Java" group. > To post to this group, send email to > google-appengine-j...@googlegroups.com. > To unsubscribe from this group, send email to > google-appengine-java+unsubscr...@googlegroups.com<google-appengine-java%2bunsubscr...@googlegroups.com> > . > For more options, visit this group at > http://groups.google.com/group/google-appengine-java?hl=en. > > -- You received this message because you are subscribed to the Google Groups "Google App Engine for Java" group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
