Add special note for EDD and EF

[rkac-bw]

🎟️ Tracking

📔 Objective

Add specific info in regards to implementing EDD process for Entity framework Only Databases with Code Migrations (Self host for example)

⏰ Reminders before review

• Contributor guidelines followed
• All formatters and local linters executed and passed
• Written new unit and / or integration tests where applicable
• Protected functional changes with optionality (feature flags)
• Used internationalization (i18n) for all UI strings
• CI builds passed
• Communicated to DevOps any deployment requirements
• Updated any necessary documentation (Confluence, contributing docs) or informed the documentation
  team

🦮 Reviewer guidelines

• 👍 (:+1:) or similar for great changes
• 📝 (:memo:) or ℹ️ (:information_source:) for notes or general info
• ❓ (:question:) for questions
• 🤔 (:thinking:) or 💭 (:thought_balloon:) for more open inquiry that's not quite a confirmed
  issue and could potentially benefit from discussion
• 🎨 (:art:) for suggestions / improvements
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• 🌱 (:seedling:) or ♻️ (:recycle:) for future improvements or indications of technical debt
• ⛏ (:pick:) for minor or nitpick changes

[github-actions]

Checkmarx One – Scan Summary & Details – 99c56dcc-ce4c-4f12-b2c1-b42937e06d81

No New Or Fixed Issues Found

[Hinton]

Is this needed? To my knowledge we don't use EF migrations for cloud and unified has no requirement for EDD.

[withinfocus]

Is this needed? To my knowledge we don't use EF migrations for cloud and unified has no requirement for EDD.

EF migrations are used for SM in the cloud right? I'd rather be consistent in our approach nonetheless though. It would be ideal to see a PR that includes EDD-prescribed changes both in a traditional DbUp migration script as well as an EF one.

[withinfocus]

Your lint is failing -- make sure that's running locally for you per the setup guide.

[withinfocus]

Suggested change

	## EF-Only Databases with Code Migrations
	## EF-only databases with code migrations

[Hinton]

No, SM uses regular migrations since using the EF framework for half our tables and hand written for the rest would be very difficult get running and even harder to follow.

For the delete scenario we should be fine having EF migrations that immediately delete the value. In cloud this means adding a migration for the next release to delete the value from the DB. If the value is required we make it not-required in the current release. This does mean we lose the ability to roll back using EF migrations, but that shouldn't occur on self-hosted instances.

There are more complex scenarios like column rename that requires some juggling with EF. And requires 3 deployments + 1 data migration.

1. Add column new, update code to write both old and new. <- DB & code deploy.
2. Run DB migration copying all old to new. <- DB
3. Removing code references to old. <- Code
4. Remove old from database. <- DB

[eliykat]

Is there a consensus here? I need to drop some columns currently - which approach should I be using?

Regarding the PR itself - it would be useful to have a timeline showing both database frameworks side-by-side. e.g.

---

Example: dropping a column

Step #	C# Entity	MSSQL	EF
1.	No change	Give the parameter a default value in all sprocs	No change
Release
2.	Delete the property	No change	Configure the column as a shadow property (no migration)
Release
3.	No change	Drop the column and remove corresponding sproc parameters (migration)	Delete the shadow property (migration)

---

Maybe there is a better way to represent this.

[eliykat]

How do I do this? I had a look at https://learn.microsoft.com/en-us/ef/core/modeling/shadow-properties but it wasn't obvious how that maps to our implementation.