Failed to restore DB

[gerhard (Gerhard Schlager)]

@Rasin

The error maybe:

PG::UniqueViolation: ERROR:  could not create unique index "unique_index_categories_on_slug"
DETAIL:  Key (COALESCE(parent_category_id, '-1'::integer), slug)=(5, ) is duplicated.

@daniel I think the migration in FIX: Add unique index to prevent duplicate slugs for categories · discourse/discourse@c71da3f · GitHub needs to make sure the column values are unique before creating the unique index.