# upgrade sub-generator

Upgrades the application to a newer generator-jhipster version.

The upgrade process generates 4 commits:

- the reference application
- a merge commit with unrelated histories
- the upgrade application
- a merge commit to apply the upgrade commit to the existing application

## Upgrading from v7

To upgrade to v8 you need to upgrade to v7.9.4 before due to node v18/v20 compatibility.
If you use blueprint that uses jhipster v7, you need to use [jhipster-migrate](https://github.com/jhipster/generator-jhipster-migrate/).

## Changing the application configuration

It's possible to apply configuration changes using the upgrade process.

For example to switch databases:

```
jhipster upgrade --apply-config --db postgresql
```

To remove admin ui:

```
jhipster upgrade --apply-config --no-with-admin-ui
```

For more configuration options run:

```
jhipster app --help
```