Hasan Savran takes us through optimistic concurrency with Cosmos DB:
To handle this problem, usually developers use a column like LastUpdateDt. You bring this column to Frontend and post it back to database with updated model. If LastUpdateDt hasn’t changed updates goes into database. If LastUpdateDt is changed, that means somebody else updated this model and your code rejects changes.
In this post, I will try to answer questions like “ How do we do this in Azure Cosmos DB?”“Do I need to do all that logic manually by using Cosmos DB SDK? “ I will use Cosmos DB’s REST API to demo how Cosmos DB handles Optimistic Concurrency Control automatically. If you have experience developing any REST API, you might be familiar with headers like If-Match or If-None-Match. These HTTP headers controls what should be updated or not. Also, you can use them for caching too since they check which item is updated or not, you may need to cache items until they are changed.
Hasan has a demo for us as well, so check it out.