migration | Simple and pragmatic migrations for Go applications | Data Migration library

I'm thinking the suspect is an unsuccessful migration. Let's undo it and try again

change the posts migration post_id and author_id to this :

I solved my issue by using Docker Compose Wait. Essentially, it adds a wait loop that samples the DB container, and only when it's up, runs migrations and seeds the DB.

My next problem was: those seeds ran every time the container was run - I solved that by instead running a script that runs the seeds, and touchs a semaphore file. If the file exists already, it skips the seeds.

There are a couple of things to try out and fix:

You probably don't need the many2many attribute to load the DonationDetail slice, since they can be loaded only with DonationID. If you have a foreign key, you can add it like this:

The best idea is to keep production and development migrations the same and while developing you clean migrations before pushing the code and you should push migrations into your Version Control System too.

In development, you might end up deleting a table and re-creating it so make sure you don't push the un-intended migrations. The thing is you should treat migrations as code, not an automated script. I have done a lot of mistakes in the past, so, I came to the conclusion of including migrations in code. and that's effective and gives more control.

Moreover you might have to do data migrations in production, how will you do if you wont push the code?

This is not straightforward and will need some manual interventions and it depends on what do you want to do in the future

• If the tables that already exist in the database have a stable design and won't be changed or you can do the changes manually using SQL statements then set managed = False to the models' meta, this will make Django skip making migrations for those models

• If you want to keep the power of migration in the new project for all models then this will more complex

  1. Delete all your migrations
  2. You need to make your models equivalent to your database, you can set managed=False for new models like Users
  3. Run python manage.py makemigrations, this will create the structure of the initial database.
  4. Fake running the migrations python manage.py migrate --fake
  5. Dump the records of django_migrations table
  6. Create a new empty migration (with --empty) and add the SQL statements of the django_migrations table to it using migrations.RunSQL()
  7. now fake again so you skip that new migration.
  8. Now you are ready to use migrations as usual.

When installing new database, you will just need to run python manage.py migrate

The issue was actually a breaking change for the new version of EF Core 5.0, which I apparently looked over. https://docs.microsoft.com/en-us/ef/core/what-is-new/ef-core-5.0/breaking-changes#toview

Your migration will result in such table:

Your problem is that you have set SESSION_CONNECTION=session, but your SESSION_DRIVER=default, so you have to use SESSION_DRIVER=database in your .env. See the config/session.php: