Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Probe-to-build SIP materializes and rescans the whole probe side (ACCUMULATE + RESULT_COLLECTOR/READ_FTABLE) to seed the build-side semi mask. When the probe side is at least as large as the build side, the mask can prune at most buildCard rows while materialization pays collect + rescan over probeCard rows, so the optimization cannot pay off: keep the plain pipelined hash join. The LIMIT-pushdown path (probeLimit) is exempted since its capped probe still benefits from the mask.
Motivating case: CardinalityTest.TestMultiParentPackedScan dataset, where the probe-side rescan produced ~2253 single-key batches (flat-a/unflat-b factorized layout replayed one key per batch). Skipping the unprofitable SIP removes the probe-side materialization round-trip (measured ~4.3ms there) with byte-identical results.
Skipping an optimization is correctness-safe by construction. Verified locally: optimizer_test 24/24, CardinalityTest.* 7/7, join-related e2e (join/Join) 22/22.