UnorderedObjectListWarning in Django Paginator over large unordered QuerySets

Paginating a large Django QuerySet without an explicit order_by() clause triggers UnorderedObjectListWarning because OFFSET/LIMIT pagination over an unordered result set can skip or duplicate rows across page boundaries. Django treats this condition as advisory rather than fatal, leaving the ordering decision unresolved for the developer.

The tension is practical: enforcing a default ordering could break existing applications that rely on implicit insertion order, while leaving pagination unordered preserves backward compatibility at the expense of deterministic results. On large tables, offset-based pagination also degrades as the offset increases because the database must scan and discard rows, whereas keyset pagination using a WHERE clause on a sorted column avoids that cost. However, keyset pagination requires a unique, stable ordering column and is not a transparent replacement for Paginator. Exact triggering conditions and warning text may vary between Django versions, so behavior should be confirmed against the specific release source.

Adding order_by('pk') may suppress the warning without matching business sort requirements, potentially masking underlying data-modeling issues.

What criteria should determine whether to resolve the warning by adding an explicit ordering versus redesigning the view for keyset pagination? Are there cases where high-offset pagination remains acceptable on large tables despite the warning? How can an application maintain backward compatibility while ensuring deterministic page boundaries when the data model lacks a natural unique sort key?