docs(meta-db): warn that SUPERSET_META_DB_LIMIT truncates tables before joins#41302
Open
rusackas wants to merge 1 commit into
Open
docs(meta-db): warn that SUPERSET_META_DB_LIMIT truncates tables before joins#41302rusackas wants to merge 1 commit into
rusackas wants to merge 1 commit into
Conversation
…re joins Addresses #36304. The Superset meta database applies SUPERSET_META_DB_LIMIT (default 1000) to each underlying table before the in-memory join runs, so a join over tables larger than the limit can silently return incomplete or empty results. Document this caveat near the existing SUPERSET_META_DB_LIMIT prose. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Contributor
Code Review Agent Run #ae66a4Actionable Suggestions - 0Review Details
Bito Usage GuideCommands Type the following command in the pull request comment and save the comment.
Refer to the documentation for additional commands. Configuration This repository uses Documentation & Help AI Code Review powered by |
3 tasks
✅ Deploy Preview for superset-docs-preview ready!
To edit notification comments on pull requests, go to your Netlify project configuration. |
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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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.
SUMMARY
Addresses #36304. When the Superset meta database (
ENABLE_SUPERSET_META_DB) joins across underlying databases,SUPERSET_META_DB_LIMIT(default 1000) is applied to each underlying table before the in-memory join runs, not to the final result. If any joined table has more rows than the limit, only the firstSUPERSET_META_DB_LIMITrows of that table are read, so matching rows can be silently dropped and the join can return incomplete or empty results with no error. The existing docs mention the per-table limit but don't warn that it can silently produce wrong results. This adds a:::warningadmonition next to the existingSUPERSET_META_DB_LIMITprose explaining the behavior and the workaround (raise the limit above your largest joined table, or set it toNonefor small tables). Docs-only; the underlying behavior is left for a separate fix decision, so the issue stays open.TESTING INSTRUCTIONS
Docs only. No code changes.
ADDITIONAL INFORMATION