Scaling application
I am on a team designing a large enterprise/commercial online project.

The specifications is 100% scalability, so we are looking to go cloud as far as the hardware goes..
 
There is a central platform that we are building with plug ins for external apps/plug ins etc

End users currently log into the platform and select services that this platform has to offer.

My question is ... if from 1000 users it goes to 1Million users how would we scale the database, for scalability would it be better to shrad the database right away when there are only 100 users ?
Scaling application
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I am on a team designing a large enterprise/commercial online project.

The specifications is 100% scalability, so we are looking to go cloud as far as the hardware goes..
 
There is a central platform that we are building with plug ins for external apps/plug ins etc

End users currently log into the platform and select services that this platform has to offer.

My question is ... if from 1000 users it goes to 1Million users how would we scale the database, for scalability would it be better to shrad the database right away when there are only 100 users ?