Improve experience for optimistic concurrency

[ajcvickers]

This is a grouping of related issues. Feel free to vote (👍) for this issue to indicate that this is an area that you think we should spend time on, but consider also voting for individual issues for things you consider especially important.

---

This an "epic" issue for the theme of improvements to optimistic concurrency. Specific pieces of work will be tracked by linked issues.

Backlog

• Optimistic Offline Lock #2195
• Allow opt-out of optimistic concurrency/rows affected check in the model #10443
• Add option to disable concurrency checking at the SaveChanges level #19056
• Data Seeding: Generate leaner SQL #9998
• PERF: Omit SELECT @@ROWCOUNT; when we are executing just a single statement #7037
• Update of an non-existing, optional entity ends in DbUpdateConcurrencyException #19508
• Add support for INSERT IGNORE / ON CONFLICT DO NOTHING #16949
• Improve concurrency control for owned types #18529
• Provide a way to force ef to check ConcurrencyToken #18536
• Throw a better exception message when concurrency token is an array #18505
• Improve optimistic concurrency exception #22269
• Support SELECT FOR UPDATE / UPDLOCK (pessimistic concurrency) #26042