This is a demo project trying to solve common challenge - insert new entity into a DB Table only if the entity does not exist yet. It has to work in highly concurrent system without unique key violation errors or deadlocks.

Two strategies are implemented:

• Synchronize addition of new items with DB locks
• Synchronize addition of new items with back-end service

• .NET Standard 2.1
• ASP .NET Core 3.1
• Entity Framework Core 3.1

• The project is implemented following the principles of Clean Architecture
• Repository Pattern
• ASP.NET CORE template