pola-rs/polars · error

{:?}

Error message

{:?}

What it means

Interpolation panic in the parquet statistics reader macro: a value failed to deserialize into the expected typed statistics variant (the error's Display is inlined as {:?}). Encountered with malformed or mismatched statistics in the parquet footer.

Source

Thrown at crates/polars-parquet/src/arrow/read/statistics.rs:273

            (D::Binary, _) => rmap!(@binary),
            (D::LargeBinary, _) => rmap!(@binary),
            (D::Utf8, _) => rmap!(@string),
            (D::LargeUtf8, _) => rmap!(@string),

            (D::BinaryView, _) => rmap!(@binary),
            (D::Utf8View, _) => rmap!(@string),

            (D::FixedSizeBinary(_), _) => {
                rmap!(expect_fixedlen, |x: Option<Vec<u8>>| ParquetResult::Ok(
                    x.map(|x| FixedSizeBinaryArray::new(
                        self.field.dtype().clone(),
                        x.into(),
                        None
                    ))
                ))
            },

            other => todo!("{:?}", other),
        };

        Ok(ArrowColumnStatistics {
            null_count,
            distinct_count,

            min_value,
            max_value,
        })
    }
}

/// Deserializes the statistics in the column chunks from a single `row_group`
/// into [`Statistics`] associated from `field`'s name.
///
/// # Errors
/// This function errors if the deserialization of the statistics fails (e.g. invalid utf8)
pub fn deserialize_all(

View on GitHub (pinned to 68506541d2)

Solutions

1. Statistics deserialization hit an unexpected type; ensure the parquet file's statistics match the column's physical type.
2. Read the file with statistics disabled if they are malformed.

When it happens

Trigger: This panic/expect fires when execution reaches an unguarded state described by: "{:?}". Typical triggers: unsupported dtype or feature-gated code path reached at runtime, invalid user input or environment variable value, calling API methods in the wrong order or on mismatched types, or data (lengths, offsets, ranges) violating the function's preconditions.

Common situations: Encountered when input data or configuration does not meet the preconditions of the throwing code path ("{:?}"). Common cases: missing Cargo feature flags, mismatched dtypes/lengths between arrays or series, out-of-range temporal values, malformed environment variables, or operations on unsupported/complex nested types.

AI-assisted analysis of pola-rs/polars@68506541d2 (2026-08-19). Data as JSON: /api/errors/ba4c33fdb209bf92. Report an issue: GitHub.