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`overwrite` parameter in `to_parquet` does nothing

Open Beginner friendly
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Assessment

Difficulty
2/5
Estimated time
1-3 hours
Newbie friendliness
75/100
Issue type
Bug
Clarity
Clearly specified
Activity status
Active
Tech stack
python
Domain
backend, databases

Research direction

Look at the write_parquet method in the Python bindings, likely in a file like src/duckdb_python/relation.py or similar. The overwrite parameter should be passed to the underlying C++ function. Check how other parameters are handled and trace the call to see where overwrite is ignored. Write a test using the provided reproduction script to verify the fix.

Written by the indexing model from the issue text.

Description

needs triage
What happens?

When using to to_parquet and setting overwrite=False, the file is still overwritten. No warning or exception is raised.

To Reproduce
import duckdb

con = duckdb.connect()

con.sql("SELECT 1 as test").write_parquet("test.parquet")

con.close()

con = duckdb.connect()

con.from_parquet("test.parquet").show()

con.sql("SELECT 2 as test").write_parquet("test.parquet", overwrite=False)

con.from_parquet("test.parquet").show()

OUTPUT

┌───────┐
│ test  │
│ int32 │
├───────┤
│     1 │
└───────┘

┌───────┐
│ test  │
│ int32 │
├───────┤
│     2 │
└───────┘
OS:

macOS Tahoe 26.6.2

DuckDB Package Version:

1.5.5

Python Version:

3.13.15

Full Name:

Luke Strange

Affiliation:

The Data City

What is the latest build you tested with? If possible, we recommend testing with the latest nightly build.

I have tested with a stable release

Did you include all relevant data sets for reproducing the issue?

Not applicable - the reproduction does not require a data set

Did you include all code required to reproduce the issue?
  • Yes, I have
Did you include all relevant configuration to reproduce the issue?
  • Yes, I have
Dominant language
Python
Stars
186
Forks
113
Avg merge
22h 45m
Merged PRs (30d)
14

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