Change type of Datastore field to Text from String?

Question

I can't seem to do this. The list that the app engine datastore viewer does not contain Text as an option. I had to change my fields because some of my values were too long for String, but now I can't retroactively fix my old entries.

Answer 1

To change the property type used by the old entities, you need to manually update each of them.

This can be easily and efficiently accomplished using the mapper API. This guide explains how to use this API.

You may also want to read this blog post by Nick Johnson.

Answer 2

You don't have to fix your old entries. The old ones should work as is, and the new ones just won't be indexed.

See http://groups.google.com/group/google-appengine/browse_thread/thread/282dc825f9c46684 .