Unable to generate an explicit migration in entity framework

Question

I am adding a new migration but this message shows:

Unable to generate an explicit migration because the following explicit migrations are pending:

Answer 1

If you haven't used Update-Database you can just delete it. If you've run the update then roll it back using Update-Database -TargetMigration "NameOfPreviousMigration", then delete it.

Reference: http://elegantcode.com/2012/04/12/entity-framework-migrations-tips/

I copied this text directly from here: How do I undo the last Add-Migration command?

Answer 2

I had the same problems and was only able to resolve it running Add-Migration 'MigrationName' -Force

With -Force being the important part.

Answer 3

Tip: It's always good to use the -Script switch for migration commands if you're not sure. It also really helps understand what Update-Database actually does.

I run the following to update the database, then I get a script I can apply manually (or just run it again without the -Script tag).

For Update-Database I would run the following :

Update-Database -Script -ConfigurationTypeName Configuration_ASPNETIdentity -ConnectionStringName SQL_AzureLive

Where SQL_AzureLive is the named connection string in my config.

Then I can verify the SQL looks right, apply it and be done. As many others have said if the connection string is wrong or invalid you'll get this error.

Answer 4

It tells you that there is some unprocessed migration in your application and it requires running Update-Database before you can add another migration.

Answer 5

Scenario

• I am working in a branch in which I created a new DB migration.
• I am ready to update from master, but master has a recent DB migration, too.
• I delete my branch's db migration to prevent conflicts.
• I "update from master".

Problem

After updating from master, I run "Add-Migration my_migration_name", but get the following error:

Unable to generate an explicit migration because the following explicit migrations are pending: [201607181944091_AddExternalEmailActivity]. Apply the pending explicit migrations before attempting to generate a new explicit migration.

So, I run "Update-Database" and get the following error:

Unable to update database to match the current model because there are pending changes and automatic migration is disabled

Solution

At this point re-running "Add-Migration my_migration_name" solved my problem. My theory is that running "Update-Database" got everything in the state it needed to be in order for "Add-Migration" to work.

Answer 6

In my case (using MS Visual Studio), it was as simple as restarting Visual Studio.