Trace records that move between pages
GitHub documents following pagination links, but following links alone is not a promise of snapshot isolation. The local example uses offset pages sorted by update time, where edits can move records. Ask whether the actual source supports a snapshot or stable continuation semantics.
| Read | Items | Implication |
|---|---|---|
| First page before edit | A, B | A/B recorded |
| A edited to latest position | Order becomes B, C, D, A | Second offset page may miss C |
| Second page after edit | D, A | Dedup A still does not recover C |
Choose a completeness strategy
Prefer a documented source snapshot, a stable change feed or a bounded export with a reconciliation pass. Record the selection window and identities, not just a total. If no consistent extraction exists, label the result as an observed traversal and plan a follow-up comparison.
The total remains four, and all page requests returned success. Does that prove all four unique records were exported?
Show the worked answer
No. A duplicate can replace a missing identity while the count stays unchanged. Compare identities or a source-supported snapshot/change boundary.