pitrou commented on code in PR #43726:
URL: https://github.com/apache/arrow/pull/43726#discussion_r1745775278
##########
cpp/src/arrow/dataset/file_parquet.cc:
##########
@@ -366,8 +366,14 @@ std::optional<compute::Expression>
ParquetFileFragment::EvaluateStatisticsAsExpr
const parquet::Statistics& statistics) {
auto field_expr = compute::field_ref(field_ref);
+ bool may_have_null = !statistics.HasNullCount() || statistics.null_count() >
0;
// Optimize for corner case where all values are nulls
- if (statistics.num_values() == 0 && statistics.null_count() > 0) {
+ if (statistics.num_values() == 0) {
+ // If `statistics.HasNullCount()`, it means the all the values are nulls.
+ //
+ // If there are no values and `!statistics.HasNullCount()`, it might be
Review Comment:
```suggestion
// If there are no non-null values, column `field_ref` in the fragment
might be
```
--
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]
