apache / apache/iceberg-python

Bug: dynamic_partition_overwrite silently skips spec-0 manifests after partition spec evolution

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Description

## Summary

`dynamic_partition_overwrite` produces incorrect results when a table has undergone
partition spec evolution. Manifests written under older specs are silently skipped
by the manifest pruning logic introduced in #3011, leaving stale data files that
should have been deleted.

## Root cause

In `Table.dynamic_partition_overwrite` (`table/__init__.py`), the delete predicate
is built using only the **current** partition spec:
```python
delete_filter = self._build_partition_predicate(
partition_records=partitions_to_overwrite,
spec=self.table_metadata.spec(), # always current spec
schema=self.table_metadata.schema()
)
```

A snapshot with mixed `partition_spec_id`s (spec-0 and spec-1 manifests) passes
this single predicate to `_DeleteFiles`. The manifest evaluator in `_build_partition_projection`
uses `inclusive_projection(schema, spec)` — when projecting a spec-1 predicate
(e.g. `category=A AND region=us`) through spec-0 (which only has `category`), the
`region` reference has no corresponding partition field, causing the evaluator to
incorrectly skip spec-0 manifests entirely.

## Reproduction
```python
import tempfile, pyarrow as pa
from pyiceberg.catalog import load_catalog
from pyiceberg.schema import Schema
from pyiceberg.types import NestedField, StringType, LongType
from pyiceberg.partitioning import PartitionSpec, PartitionField
from pyiceberg.transforms import IdentityTransform

schema = Schema(
NestedField(1, "category", StringType(), required=False),
NestedField(2, "region", StringType(), required=False),
NestedField(3, "value", LongType(), required=False),
)
spec_v0 = PartitionSpec(
PartitionField(source_id=1, field_id=1000, transform=IdentityTransform(), name="category")
)

with tempfile.TemporaryDirectory() as warehouse:
catalog = load_catalog("test", **{"type": "sql", "uri": f"sqlite:///{warehouse}/catalog.db", "warehouse": f"file://{warehouse}"})
catalog.create_namespace("default")
table = catalog.create_table("default.test", schema=schema, partition_spec=spec_v0)

# Write under spec 0
table.append(pa.table({"category": ["A","A","B"], "region": [None,None,None], "value": [1,2,10]}))

# Evolve spec
with table.update_spec() as u:
u.add_field("region", IdentityTransform(), "region")
table = catalog.load_table("default.test")

# Write under spec 1
table.append(pa.table({"category": ["A","B"], "region": ["us","us"], "value": [100,200]}))

# Overwrite category=A — should delete ALL A rows (both specs)
table.dynamic_partition_overwrite(
pa.table({"category": ["A"], "region": ["us"], "value": [999]})
)

result = table.scan().to_arrow().to_pydict()
a_values = [v for c,v in zip(result["category"], result["value"]) if c == "A"]
print(a_values) # BUG: prints [1, 2, 100, 999] — stale rows from spec-0 not deleted
# EXPECTED: [999]
```

## Fix

Build the delete predicate **per historical spec** present in the snapshot, projecting
the new data files' partition values into each spec's coordinate space before evaluating.
PR with fix and regression tests to follow.

## Related
- #3011 (introduced the manifest pruning optimization)
- #1108 (prior related fix by @Fokko for spec evolution in manifest rewriting)

Contributor guide

No contributing guide indexed for this repository

Research direction

Start in table/__init__.py at Table.dynamic_partition_overwrite, then trace _build_partition_projection and the manifest-pruning change from #3011. Reproduce the mixed spec-0/spec-1 snapshot described in the issue and compare with the prior related fix in #1108. Done means a regression test confirms overwriting removes matching rows from both historical specs without deleting unrelated data.

Written by the indexing model from the issue text.

Assessment

Tech stack
python
Domain
databases
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Active
Clarity
Clearly specified
Newbie friendliness
70/100

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