# NEXTLY_CORE_DESTRUCTIVE_REFUSED

Bringing Nextly's own tables up to date needs a destructive change, which `nextly migrate` makes only with `NEXTLY_ALLOW_CORE_DESTRUCTIVE=1`.

## Cause

Bringing Nextly's own tables up to date needs a destructive change, which `nextly migrate` makes only with `NEXTLY_ALLOW_CORE_DESTRUCTIVE=1`.

Before the app's migrations, `nextly migrate` brings Nextly's own tables up to date. A change there that would drop a table or column, or fail on rows already stored, is refused by default: it usually means the installed `nextly` and the database come from different releases.

## Fix

* Check that the installed version of `nextly` is the one the database was last migrated with, and read that release's notes.
* Once you are sure the change is intended, run `nextly migrate` with `NEXTLY_ALLOW_CORE_DESTRUCTIVE=1` set.

## Example

```text
✗ Core schema reconciliation requires destructive operations.
  Why:  drops column 'nextly_users.legacy_role'
        drops table 'nextly_sessions_old'
        This usually means a Nextly version mismatch.
  Next: Set NEXTLY_ALLOW_CORE_DESTRUCTIVE=1 to proceed (see release notes).
  Docs: https://nextlyhq.com/docs/cli/errors/nextly-core-destructive-refused  (NEXTLY_CORE_DESTRUCTIVE_REFUSED)
```