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Suppose I have 2 entity kinds A and B, and I have a transaction that updates an entity in A and an entity in B (so a transaction across entity kinds).

I was wondering whether, when backing up my datastore (through Datastore Administration), the entities of A and B in the backup are guaranteed to be logically consistent with respect to that transaction?

I could imagine that the backup backs up everything from A, then everything from B, and the transaction happening somewhere in the middle, in which case the backup could have the change to B but not to A.

Extra question: If the backup is guaranteed to be consistent, is this something that is only possible by using internals, or is this something you could achieve using the API?

Dan McGrath
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Remko
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1 Answers1

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The Datastore backup feature described here does not provide any consistency guarantees.

To get a consistent view of multiple entity groups, you can use a cross-group transaction, but this would require writing custom code to do the backup.

Ed Davisson
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