Starting from release 5.0.0, Alembic is used for managing database migrations.

Run `alembic upgrade head` from the aurweb root directory to upgrade your
database after upgrading the source code to a new release.

When upgrading from 4.8.0, you also need to execute the following manual SQL
statements before doing so.

1. Add new columns to store the timestamp and UID when closing requests:

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ALTER TABLE PackageRequests ADD COLUMN ClosedTS BIGINT UNSIGNED NULL DEFAULT NULL;
ALTER TABLE PackageRequests ADD COLUMN ClosedUID INTEGER UNSIGNED NULL DEFAULT NULL;
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2. Add a new column to store backup email addresses:

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ALTER TABLE Users ADD COLUMN BackupEmail VARCHAR(254) NULL DEFAULT NULL;
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