XG Transactions and development server

[PK]

I see the following on the dev server:

"BadRequestError: can't operate on multiple entity groups in a single transaction"

I think that it happens because although all my entity activity is in the same TG, I also use blobs that behind the scenes access the datastore at the "non ancestor" TG. This is something I had not thought of but I am wondering whether it should now be an issue at all with the HRD? Is it just one more dev server limitation?  (I do have the --high_replication option in the command line).

Thanks

[Juna]

It may be not your problem but this same error happened if you are with Java and using GAE SDK 1.5.5 because Google included jar datanucleus-appengine.1.0.9 by mistake (where XG transactions are not supported). They notice and ask you to update that jar to datanucleous-appengine.1.0.10final , you can find it here.

Another reason may be that XG transactions are limited to operations between a max of five entity groups, but I don't know if this is the exception returned in that case.

[P K]

Thanks Juna,

I am in Python and I have only one entity group of my own in this case.

Could somebody from Google comment what the expected behavior should
be and whether the SDK server has been retrofitted to support XG
transactions?

Thanks,
PK

[PK]

To close this thread, It turns out that XG transactions are not turned on automatically; it is controlled per transaction and an API has to be called first to do this. This is explained in the documentation but I had missed it, sorry... After I turned the XG on, things work as expected on the dev server.