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EF Migrations: Rollback last applied migration?

This looks like a really common task, but I can't find an easy way to do it.

I want to undo the last applied migration. I would have expected a simple command, like

PM> Update-Database -TargetMigration:"-1"

Instead, all I can come up with is:

PM> Get-Migrations

Retrieving migrations that have been applied to the target database.
201208012131302_Add-SystemCategory
201207311827468_CategoryIdIsLong
201207232247409_AutomaticMigration
201207211340509_AutomaticMigration
201207200025294_InitialCreate

PM> Update-Database -TargetMigration:"CategoryIdIsLong"

(At least I can use just the name, skipping the timestamp...)

Is there an easier way?

Sad, here we are years later and no one actually read the question.

J
Jazimov

I want to add some clarification to this thread:

Update-Database -TargetMigration:"name_of_migration"

What you are doing above is saying that you want to rollback all migrations UNTIL you're left with the migration specified. Thus, if you use GET-MIGRATIONS and you find that you have A, B, C, D, and E, then using this command will rollback E and D to get you to C:

Update-Database -TargetMigration:"C"

Also, unless anyone can comment to the contrary, I noticed that you can use an ordinal value and the short -Target switch (thus, -Target is the same as -TargetMigration). If you want to rollback all migrations and start over, you can use:

Update-Database -Target:0

0, above, would rollback even the FIRST migration (this is a destructive command--be sure you know what you're doing before you use it!)--something you cannot do if you use the syntax above that requires the name of the target migration (the name of the 0th migration doesn't exist before a migration is applied!). So in that case, you have to use the 0 (ordinal) value. Likewise, if you have applied migrations A, B, C, D, and E (in that order), then the ordinal 1 should refer to A, ordinal 2 should refer to B, and so on. So to rollback to B you could use either:

Update-Database -TargetMigration:"B"

or

Update-Database -TargetMigration:2

Edit October 2019:

According to this related answer on a similar question, correct command is -Target for EF Core 1.1 while it is -Migration for EF Core 2.0.


The name of the migration with index 0 is $InitialDatabase.
Thanks. Are there any $(name) values to refer to other index positions, such as $LatestDatabase, or something like that?
I don't know. I haven't been able to find any by simple googling. Maybe browsing the EF source code would reveal them?
FYI, we just ran into this and were looking to do the same thing as OP... using ls variable:* it looks like $InitialDatabase is simply a PowerShell variable defined as 0, there aren't any other ones defined, even in the current EF source code. And, get-migrations doesn't return anything, it only writes to the console, so you can't iterate over the objects returned...
This should be the answer
C
Caltor

As of EF 5.0, the approach you describe is the preferred way. So

PM> Update-Database -TargetMigration:"NameOfSecondToLastMigration"

or using your example migrations

PM> Update-Database -TargetMigration:"CategoryIdIsLong"

One solution would be to create a wrapper PS script that automates the steps above. Additionally, feel free to create a feature request for this, or better yet, take a shot at implementing it! https://github.com/dotnet/ef6


Another detail: If you have an existing Manual Migration you need to roll back to, but realized your "Down" method doesn't really roll things back properly, you can just edit and save it, then rerun update-database -target... until it rolls back properly. Modifying the Manual Migration after the fact - after you've already applied it - doesn't turn it into something that's not allowed to be edited.
This does not work for me. All I get is "specified target migration "-1" does not exist.
@tutiplain Look at his second code block. You quoting what he wishes existed, not what does exist.
what is the correct way of doing this using dotnet command? Sorry i could not find in the documentation or i am missing something. Tried via entityframeworktutorial.net/efcore/… any suggestions?
-TargetMigration didn't work BUT -Migration did, EF Core 5.0.7
M
MaciejLisCK

In EntityFrameworkCore:

Update-Database 20161012160749_AddedOrderToCourse

where 20161012160749_AddedOrderToCourse is a name of migration you want to rollback to.


GEM! It took me a while to find this answer (as they've changed it for .NET Core). Definitely worth an upvote!
You don't need to include the date/time. You can just put in the name.
This does not work for me... it will say "Done" but all migrations after the one I specify still remain. And none of the "Down" code in any of those migrations has been executed.
one can also run back to a specific migration like that: Update-Database -Migration: "AddedOrderToCourse" Especially when using blanks in migration names, this is the way to do it. (i.e. Update-Database -Migration "Added Order to Course")
Q
QmlnR2F5

I realised there aren't any good solutions utilizing the CLI dotnet command so here's one:

dotnet ef migrations list
dotnet ef database update NameOfYourMigration

In the place of NameOfYourMigration enter the name of the migration you want to revert to.

Then you can remove all the reverted migrations for good using

dotnet ef migrations remove

T
Timtech

The solution is:

Update-Database –TargetMigration 201609261919239_yourLastMigrationSucess

This is already said in the question, the asker already knew this. I don't see how this helps, maybe you could make that clearer?
this answer is more concise. TY Max!
f
feli_jane

EF CORE

PM> Update-Database yourMigrationName

(reverts the migration)

PM> Update-Database

worked for me

in this case the original question (yourMigrationName = CategoryIdIsLong)


The previous solution doesn't work for EF Core , parameter error, whereas this two step solution worked, I was able to remove-migration after this whereas before I got an error message: The migration '20210201060139_cascadeDelete' has already been applied to the database. Revert it and try again. when remove-migration was tried.attempeted.
S
Sean Saúl Astrakhan

In EF Core you can enter the command Remove-Migration in the package manager console after you've added your erroneous migration.

The console suggests you do so if your migration could involve a loss of data:

An operation was scaffolded that may result in the loss of data. Please review the migration for accuracy. To undo this action, use Remove-Migration.


This only works when the migration hasn't been applied on the database yet.
m
mattylantz
update-database 0

Warning: This will roll back ALL migrations in EFCore! Please use with care :)


A
Amos

Additional reminder:

If you have multiple configuration type, you need to specify the [ConfigurationName]

Update-Database -Configurationtypename [ConfigurationName] -TargetMigration [MigrationName]

L
LCarter

I run mine through my (BASH GIT) console also running Entity Framework Core. Update-Database commands will not work outside of the package console and I have to use the donet ef commands.

donet ef database update [Name of previous Migration]

This will run the protected override void Down(MigrationBuilder migrationBuilder) method of your current migration and all of the others to get back to the version of the DB you set it to.

I also use the -p [migration project] -s [Project Solution]. This also allows it to point to my appsettings.[Enviorment].json where my password to access DB is stored.

export ASPNETCORE_ENVIRONMENT=[ENVIORMENT]; donet ef database update [Name of previous Migration] -p [Migration Project Name] -s [Solution Name]

A lot of this might be known but wanted to give detail in case your first time doing.


G
Gjaa

EF CORE

Update database to the previous point

update-database CategoryIdIsLong

And then, remove the bad migration

remove-migration

C
Chris Halcrow

I'm using EntityFrameworkCore and I use the answer by @MaciejLisCK. If you have multiple DB contexts you will also need to specify the context by adding the context parameter e.g. :

Update-Database 201207211340509_MyMigration -context myDBcontext

(where 201207211340509_MyMigration is the migration you want to roll back to, and myDBcontext is the name of your DB context)


M
Mojtaba Nava
Update-Database –TargetMigration:"Your migration name"

For this problem I suggest this link:

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


A
Alex Dresko

I found that this works when run in the Package Manager Console:

dotnet ef migrations list | select -Last 2 | select -First 1 | ForEach-Object { Update-Database -Migration $_ }

You could create a script that makes it easier.


h
hhk

In case there is a possibility for dataloss EF does not complete the update-database command since AutomaticMigrationDataLossAllowed = false by default, and roolbacks the action unless you run it with the -force parameter.

Update-Database –TargetMigration:"Your migration name" -force

or

Update-Database –TargetMigration:Your_Migration_Index -force