> ## Documentation Index
> Fetch the complete documentation index at: https://docs.getlago.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Migration to v1.43.0

Dear Lago Community, 👋

We're writing to inform you about important changes in Lago v1.43.0 that will enforce data consistency on charges and fixed charges.

# What are the changes?

## Adding NOT NULL constraint on `code` for charges and fixed charges

The `code` column on `charges` and `fixed_charges` tables will now be required (NOT NULL constraint).
Previously, this column was nullable and only populated on newly created records. Starting from v1.43.0, the database will enforce that every charge and fixed charge has a `code` value.

The backfill tasks (available since v1.42.0) will:

* Populate `charges.code` using the associated billable metric's code
* Populate `fixed_charges.code` using the associated add-on's code
* When duplicates exist within the same plan, a suffix (`_2`, `_3`, etc.) is appended to ensure uniqueness

# Why are we doing this?

These changes are made to ensure data integrity and enable the ability to independently update a charge or a fixed charge via the API. The `code` serves as a unique identifier within a plan, which is required by the new dedicated endpoints for managing charges and fixed charges.

# What should self-hosted users do?

<Note>
  Cloud users do not need to follow these instructions as the migration will be performed by the Lago Team.
</Note>

<Warning>
  If you're using a version below `v1.20.0`, please first follow the migration steps for [v1.20.0](/guide/migration/migration-to-v1.20.0), then for [v1.25.0](/guide/migration/migration-to-v1.25.0), then for [v1.28.1](/guide/migration/migration-to-v1.28.1), then for [v1.29.0](/guide/migration/migration-to-v1.29.0), then for [v1.31.0](/guide/migration/migration-to-v1.31.0), then for [v1.32.0](/guide/migration/migration-to-v1.32.0).
  Only after completing those should you proceed to v1.43.0.
</Warning>

## Migration Steps

1. Install Lago v1.42.0
2. Open a shell (bash) on your API server
3. Run the upgrade task:

```bash theme={"dark"}
bundle exec rails upgrade:perform_required_jobs
```

The task will:

* Backfill `code` on all charges that have a NULL value
* Backfill `code` on all fixed charges that have a NULL value
* Process records in batches of 1,000

<Note>
  All resources are processed in background jobs. The task will monitor progress and confirm when all records have been updated.
</Note>

<Warning>
  **Known issue:** After all jobs are enqueued, the script may appear to hang on the "Checking status" step, continuously showing remaining records without ever reaching zero.
  This is a known bug where the count includes NULL values. Once you see that all jobs have been enqueued (i.e., the `Enqueue ... per organization` section is complete), you can safely stop the script with `Ctrl+C` and proceed to the next step.
  This issue is fixed in v1.44.0.
</Warning>

4. Install Lago v1.43.0

# Get Involved

If you have any questions or encounter issues during the migration, please reach out to us via the Slack community. Our team is here to help you through this transition.

Thanks for your understanding and continued support.

The Lago Team