fix(clickhouse): report external-only DAG execution accurately - #648
Merged
Merged
Conversation
zzylol
marked this pull request as ready for review
September 11, 2026 14:21
zzylol
changed the base branch from
feat/clickhouse-exact-subtree-renderer
to
main
September 11, 2026 14:25
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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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.
An installed SQL DAG that only reads ClickHouse exact subtrees has no summary panes. Requiring summary coverage prevents that DAG from executing; reporting it as hybrid would incorrectly imply ASAP state was used.
This change skips pane coverage only when the installed query has no materialization bindings and reports successful execution as
exact_fallback/external_dag. Plans that read summary state retain their existing coverage checks. The evaluation runner also completes installation immediately when no backfill jobs are required.Before this PR, an external-only plan reached an impossible zero-pane coverage check. After this PR, the same plan can execute its typed exact leaves and local relational operators without claiming summary acceleration.
Verification: actual sketchlib #139 runtime build passed. Original o11y q07 executed through the external DAG and its decoded JSON metadata/data matched ClickHouse. Independent source review passed. A separate q27 probe exposed a one-ULP floating result difference; it is not reported as bit-exact. q09/q12 require the separate relational aggregate runtime follow-up. No performance benefit is claimed; screenshots are not applicable.
Stacked on #647. The evidence validates external DAG execution, not new ASAP workload acceleration.