paleolimbot commented on code in PR #7481:
URL: https://github.com/apache/arrow-rs/pull/7481#discussion_r2080152074
##########
parquet/src/arrow/arrow_reader/mod.rs:
##########
@@ -506,37 +525,47 @@ impl ArrowReaderMetadata {
// parquet_to_arrow_field_levels is expected to throw an error if the
schemas have
// different lengths, but we check here to be safe.
if inferred_len != supplied_len {
- Err(arrow_err!(format!(
- "incompatible arrow schema, expected {} columns received {}",
+ return Err(arrow_err!(format!(
+ "Incompatible supplied Arrow schema: expected {} columns
received {}",
inferred_len, supplied_len
- )))
- } else {
- let diff_fields: Vec<_> = supplied_schema
- .fields()
- .iter()
- .zip(fields.iter())
- .filter_map(|(field1, field2)| {
- if field1 != field2 {
- Some(field1.name().clone())
- } else {
- None
- }
- })
- .collect();
+ )));
+ }
- if !diff_fields.is_empty() {
- Err(ParquetError::ArrowError(format!(
- "incompatible arrow schema, the following fields could not
be cast: [{}]",
- diff_fields.join(", ")
- )))
- } else {
- Ok(Self {
- metadata,
- schema: supplied_schema,
- fields: field_levels.levels.map(Arc::new),
- })
+ let mut errors = Vec::new();
Review Comment:
Probably the only correctness issue would be if the supplied schema had
conflicting extension metadata (e.g., `unit: m` vs `unit: cm`). I am not sure
that the current Parquet reader ever produces extension metadata (does it read
the `ARROW:i_forget_the_exact_name key` and deserialize the schema?), so
perhaps not an issue as long as somebody remembers this when it does.
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: [email protected]
For queries about this service, please contact Infrastructure at:
[email protected]