MrDerecho opened a new issue, #586:
URL: https://github.com/apache/incubator-xtable/issues/586

   ### Search before asking
   
   - [X] I had searched in the 
[issues](https://github.com/apache/incubator-xtable/issues?q=is%3Aissue) and 
found no similar issues.
   
   
   ### Please describe the bug 🐞
   
   Description
   I am encountering an issue while using xtable to perform updates from 
Iceberg to Delta tables. Here is the observed behavior:
   
   Snapshot 0: The metadata between the Iceberg and Delta tables reconcile as 
expected.
   Snapshot 1: Erroneous metadata is generated that includes "add" and "remove" 
actions that did not actually occur. This results in a lowered row count in the 
Delta metadata compared to the source Iceberg table.
   Snapshot 2: The metadata appears to reconcile again and reflects the updated 
values accurately.
   Snapshot 3: The issue is recreated with similar discrepancies in the 
metadata.
   Additional Context:
   This behavior has been observed consistently in a sample of 30 tables.  The 
issue is in the largest of these tables with around 7 million files and 7.3 
trillion records.  This table object is "append-only", the disappeared or 
removed files on snapshot 1 are re-added in snapshot 2.  The issue seems 
cyclical, occurring every alternate snapshot.  The only error/info found in the 
logs is: "incremental sync is not safe from instant falling back to snapshot 
sync" and "truncated the string representation of a plan since it was too large"
   Steps to Reproduce:
   Use xtable to perform updates from Iceberg to Delta tables.
   Observe metadata reconciliation across snapshots.
   Expected Behavior:
   The metadata between the Iceberg and Delta tables should reconcile 
accurately across all snapshots, without erroneous "add" or "remove" actions.
   
   Actual Behavior:
   Alternate snapshots (e.g., snapshots 1 and 3) generate erroneous metadata 
with inaccurate "add" and "remove" actions, leading to a mismatch in row counts.
   
   Environment
   Tool: xtable
   Source: Apache Iceberg
   Destination: Delta Lake
   Additional Notes
   The issue might be related to how snapshots are processed or metadata is 
generated.
   
   ### Are you willing to submit PR?
   
   - [ ] I am willing to submit a PR!
   - [ ] I am willing to submit a PR but need help getting started!
   
   ### Code of Conduct
   
   - [X] I agree to follow this project's [Code of 
Conduct](https://www.apache.org/foundation/policies/conduct)
   


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