Generally, updating an entity doesn't need much actions from the developer: you just get the entity in either way, change the necessary property and invoke SubmitChanges on the context this entity is attached to. All other work (like comparing the initial and current states of this entity, generating the SQL update command and synchronizing database-generated fields - if any) is performed by the LinqConnect runtime.
However, understanding of the processes that actually take place when you update your objects may be important for better performance and stability of data modification operations in your application.
Describes how LinqConnect deals with concurrency conflicts.
Describes how LinqConnect tracks changes in entities.