branch-2.1: [fix](sort)fix merge sort may miss the limit #46072#46158
Merged
yiguolei merged 1 commit intobranch-2.1from Dec 30, 2024
Merged
branch-2.1: [fix](sort)fix merge sort may miss the limit #46072#46158yiguolei merged 1 commit intobranch-2.1from
yiguolei merged 1 commit intobranch-2.1from
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### What problem does this PR solve?
In the past, merge sort could reach this code path.
```C++
if (current->is_first()) {
if (current->block_ptr() != nullptr) {
current->block_ptr()->swap(*output_block);
_pending_cursor = current.impl;
_priority_queue.pop();
return Status::OK();
} else {
*eos = true;
}
} else {
if (current->block_ptr() != nullptr) {
for (int i = 0; i < current->block->columns(); i++) {
auto& column_with_type = current->block_ptr()->get_by_position(i);
column_with_type.column = column_with_type.column->cut(
current->pos, current->rows - current->pos);
}
current->block_ptr()->swap(*output_block);
_pending_cursor = current.impl;
_priority_queue.pop();
return Status::OK();
} else {
*eos = true;
}
}
```
When _priority_queue.size() == 1 (can be simulated with extremely skewed
data),
it might directly return without handling the limit.
Contributor
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Thank you for your contribution to Apache Doris. Please clearly describe your PR:
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Contributor
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run buildall |
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TeamCity be ut coverage result: |
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Cherry-picked from #46072