Linked tables between discrete Cache databases

There are far more efficient ways to do that.

1. Move tables you want shared into a separate Namespace with separate Code/Data databases.
2. Map your data and code into original namespace.
3. Verify that it all works as expected. So far it should work as before.
4. Create a mirroring configuration.
5. Add 2 created databases to the mirror configuration.
6. Add second server as a DR mirror.
7. Move databases to a DR mirror and mount them there.
8. (Optional) Create a namespace with 2 mirrored databases.
9. Add desired mappings on a second system.

Docs.