Reset Alembic after deleting migration folder

Question

I accidentally deleted my migrations folder. So I ran flask db init, and everything ran smoothly. But when I ran flask db migrate, it gave me this error:

INFO  [alembic.runtime.migration] Context impl SQLiteImpl.
INFO  [alembic.runtime.migration] Will assume non-transactional DDL.
ERROR [root] Error: Can't locate revision identified by '470572fac7a1'

From what I understand, it's looking for my other migration folder which is long gone. How can I solve this?

If you are OK losing your old migrations, just remove alembic and re-initialize it. Oh and also backup everything before you start, though I think that lesson has already been learned. — noslenkwah, Nov 15 '18 at 00:20

score 13 · Answer 1 · answered Nov 17 '18 at 16:56

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Delete that particular record in the table alembic_version that's in your database. There's only one varchar column called version_num, so this expression should work:

delete from alembic_version where version_num='470572fac7a1';

answered Nov 17 '18 at 16:56

txtsd

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score 9 · Answer 2 · edited Jun 12 '19 at 19:44

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Delete the /migrations directory and rename/replicate your applications database. Then start from scratch.

flask db init
flask db migrate
flask db upgrade

Now repopulate your new empty database with data from your backup.

edited Jun 12 '19 at 19:44

mx0

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answered Jun 12 '19 at 19:16

Mark Kortink

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After deleting the `/migrations` folder, make sure the new `/migrations` folder contains the following files: alembic.ini, env.py, and script.py.mako. – Brendan Jan 12 '21 at 17:17
this worked well for me. It generated an entirely new summary migration file. Now I have just have to deal with the different database name. I suppose I could drop the previous database and follow the steps again to reuse the name which I will try. – jerryb Dec 12 '21 at 22:58

score 7 · Answer 3 · answered Sep 14 '21 at 00:48

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You must delete alembic_version table in your database.

Connect to your database, and execute:

DROP TABLE alembic_version;

Please check the following answer for more details about this https://stackoverflow.com/a/32356600

answered Sep 14 '21 at 00:48

Juan Rodriguez

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score 2 · Answer 4 · answered Jul 20 '21 at 11:01

Go to versions/ inside migrations/.

If you do not see the folder versions/ or there is not a revision inside the folder versions/, type the following command to create a revision:

flask db revision

You'll get a revision inside the versions/ folder. Open it and replace the revision id with '470572fac7a1':

revision = "470572fac7a1"

Type flask db migrate again.

Should work.

score 0 · Answer 5 · answered Sep 14 '21 at 10:28

pull last version from github. And then backup your prod db. Then restore your local db. Delete your alembic table (with cascade).

Open your terminal (with venv) write code below:

rm - rf migrations
python manage.py db init

and open migrations folder. Right click on alembic.ini and choose git>rollback>ok.

python manage.py db migrate
python manage.py db upgrade

or

python manage.py db stamp head
python manage.py db migrate
python manage.py db upgrade

Reset Alembic after deleting migration folder

5 Answers5