Django: how to rearrange object ids

I've started a model with the default, automatically handled IDs Django provides.

Now I've started interfacing开发者_运维技巧 with an external system which has its own IDs for the same objects, and it would be very convenient to align my own IDs with the external system's.

However, the numerical ranges overlap, so a naive solution wouldn't work.

Is there some elegant way to alter the IDs in a safe manner? (the object have multiple foreign keys/m2ms etc)

Thanks

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I don't know if this is the best way but I would set all foreign/m2m keys to cascade updates and add a defined number to all IDs in the django db to remove the overlapping of the ranges (10k or 100K or more depeding on your data).

with that done, you can copy IDs from the other system. For safety, I would duplicate the ID columns while doing that in order to not lose the original ones... until sure all works ok