westonpace commented on a change in pull request #9947:
URL: https://github.com/apache/arrow/pull/9947#discussion_r610823327
##########
File path: cpp/src/arrow/dataset/scanner.cc
##########
@@ -67,7 +68,105 @@ Result<RecordBatchGenerator> ScanTask::ExecuteAsync() {
bool ScanTask::supports_async() const { return false; }
-Result<FragmentIterator> Scanner::GetFragments() {
+Result<ScanTaskIterator> Scanner::Scan() {
+ // TODO(ARROW-12289) This is overridden in SyncScanner and will never be
implemented in
+ // AsyncScanner. It is deprecated and will eventually go away.
+ return Status::NotImplemented("This scanner does not support the legacy
Scan() method");
+}
+
+Result<EnumeratedRecordBatchIterator> Scanner::ScanBatchesUnordered() {
+ // If a scanner doesn't support unordered scanning (i.e. SyncScanner) then
we just
+ // fall back to an ordered scan and assign the appropriate tagging
+ ARROW_ASSIGN_OR_RAISE(auto ordered_scan, ScanBatches());
+ return AddPositioningToInOrderScan(std::move(ordered_scan));
+}
+
+Result<EnumeratedRecordBatchIterator> Scanner::AddPositioningToInOrderScan(
+ TaggedRecordBatchIterator scan) {
+ ARROW_ASSIGN_OR_RAISE(auto first, scan.Next());
+ if (IsIterationEnd(first)) {
+ return MakeEmptyIterator<EnumeratedRecordBatch>();
+ }
+ struct State {
+ State(TaggedRecordBatchIterator source, TaggedRecordBatch first)
Review comment:
Whoops, yeah. Removed this, good catch.
--
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.
For queries about this service, please contact Infrastructure at:
[email protected]
