SteNicholas commented on code in PR #7669:
URL: https://github.com/apache/hudi/pull/7669#discussion_r1090241285


##########
hudi-client/hudi-flink-client/src/main/java/org/apache/hudi/table/action/commit/FlinkDeletePartitionCommitActionExecutor.java:
##########
@@ -98,4 +103,42 @@ private List<String> getAllExistingFileIds(String 
partitionPath) {
     // because new commit is not complete. it is safe to mark all existing 
file Ids as old files
     return 
table.getSliceView().getLatestFileSlices(partitionPath).map(FileSlice::getFileId).distinct().collect(Collectors.toList());
   }
+
+  /**
+   * Check if there are any pending table service actions (requested + 
inflight) on a table affecting the partitions to
+   * be dropped.
+   * <p>
+   * This check is to prevent a drop-partition from proceeding should a 
partition have a table service action in
+   * the pending stage. If this is allowed to happen, the filegroup that is an 
input for a table service action, might
+   * also be a candidate for being replaced. As such, when the table service 
action and drop-partition commits are
+   * committed, there will be two commits replacing a single filegroup.
+   * <p>
+   * For example, a timeline might have an execution order as such:
+   * 000.replacecommit.requested (clustering filegroup_1 + filegroup_2 -> 
filegroup_3)
+   * 001.replacecommit.requested, 001.replacecommit.inflight, 
0001.replacecommit (drop_partition to replace filegroup_1)
+   * 000.replacecommit.inflight (clustering is executed now)
+   * 000.replacecommit (clustering completed)
+   * For an execution order as shown above, 000.replacecommit and 
001.replacecommit will both flag filegroup_1 to be replaced.
+   * This will cause downstream duplicate key errors when a map is being 
constructed.
+   */
+  private void checkPreconditions() {
+    List<String> instantsOfOffendingPendingTableServiceAction = new 
ArrayList<>();
+    // ensure that there are no pending inflight clustering/compaction 
operations involving this partition
+    SyncableFileSystemView fileSystemView = (SyncableFileSystemView) 
table.getSliceView();
+
+    Stream.concat(fileSystemView.getPendingCompactionOperations(), 
fileSystemView.getPendingLogCompactionOperations())
+        .filter(op -> partitions.contains(op.getRight().getPartitionPath()))
+        .forEach(op -> 
instantsOfOffendingPendingTableServiceAction.add(op.getLeft()));
+
+    fileSystemView.getFileGroupsInPendingClustering()
+        .filter(fgIdInstantPair -> 
partitions.contains(fgIdInstantPair.getLeft().getPartitionPath()))
+        .forEach(x -> 
instantsOfOffendingPendingTableServiceAction.add(x.getRight().getTimestamp()));
+
+    if (instantsOfOffendingPendingTableServiceAction.size() > 0) {
+      throw new HoodieDeletePartitionException("Failed to drop partitions. "

Review Comment:
   @voonhous, IMO, users could check the `.hoodie` directory to check whether 
there is any pending compaction/clustering commit in the timeline before 
dropping the paritition by theirs. The current implementation helps users to 
skip this check step, right?



-- 
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: commits-unsubscr...@hudi.apache.org

For queries about this service, please contact Infrastructure at:
us...@infra.apache.org

Reply via email to