Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

vtexplain fails for vindex lookup queries with duplicate / equivalent values. #10996

Merged
merged 2 commits into from
Aug 17, 2022
Merged

vtexplain fails for vindex lookup queries with duplicate / equivalent values. #10996

merged 2 commits into from
Aug 17, 2022

Conversation

arthurschreiber
Copy link
Contributor

@arthurschreiber arthurschreiber commented Aug 11, 2022 •
edited by systay
Loading

Description

If a query contains an IN condition with multiple equivalent values for lookup_unique vindexes, vtexplain fails with:

Lookup.Map: unexpected multiple results from vindex <vindex>

This is due to vtexplain "simulating" that each value of the tuple in a lookup vindex query returns a result row, but when values are equivalent (e.g. 1 and "1"), only a single row should be returned.

I tried to implement this by determining the type of the column being matched against, converting each value of the tuple to that type, and then making sure vtexplain only considers non-duplicate values.

Related Issue(s)

Checklist

  • "Backport me!" label has been added if this change should be backported
  • Tests were added or are not required
  • Documentation was added or is not required

Deployment Notes

@arthurschreiber
Add a failing vtexplain test case.
55b5912 
Signed-off-by: Arthur Schreiber <arthurschreiber@github.com>
@vitess-bot
Copy link
Contributor

vitess-bot bot commented Aug 11, 2022

Review Checklist

Hello reviewers! 👋 Please follow this checklist when reviewing this Pull Request.

General

  • Ensure that the Pull Request has a descriptive title.
  • If this is a change that users need to know about, please apply the release notes (needs details) label so that merging is blocked unless the summary release notes document is included.
  • If a new flag is being introduced, review whether it is really needed. The flag names should be clear and intuitive (as far as possible), and the flag's help should be descriptive.
  • If a workflow is added or modified, each items in Jobs should be named in order to mark it as required. If the workflow should be required, the GitHub Admin should be notified.

Bug fixes

  • There should be at least one unit or end-to-end test.
  • The Pull Request description should either include a link to an issue that describes the bug OR an actual description of the bug and how to reproduce, along with a description of the fix.

Non-trivial changes

  • There should be some code comments as to why things are implemented the way they are.

New/Existing features

  • Should be documented, either by modifying the existing documentation or creating new documentation.
  • New features should have a link to a feature request issue or an RFC that documents the use cases, corner cases and test cases.

Backward compatibility

  • Protobuf changes should be wire-compatible.
  • Changes to _vt tables and RPCs need to be backward compatible.
  • vtctl command output order should be stable and awk-able.

@arthurschreiber
Fix vtexplain to handle queries with duplicate / equivalent tuple v…
277a86b 
…alues.

Signed-off-by: Arthur Schreiber <arthurschreiber@github.com>
@arthurschreiber arthurschreiber marked this pull request as ready for review August 11, 2022 15:23
@deepthi deepthi added Type: Enhancement Logical improvement (somewhere between a bug and feature) Component: vtexplain changes made to vtexplain code labels Aug 16, 2022
@systay systay merged commit 0742037 into vitessio:main Aug 17, 2022
@vitess-bot
Copy link
Contributor

vitess-bot bot commented Aug 17, 2022

I was unable to backport this Pull Request to the following branches: release-14.0.

notfelineit pushed a commit to planetscale/vitess that referenced this pull request Sep 21, 2022
@dbussink @arthurschreiber
vtexplain fails for vindex lookup queries with duplicate / equivale…
8d9a5f9 
…nt values. (vitessio#10996) (vitessio#989)

* Add a failing `vtexplain` test case.

Signed-off-by: Arthur Schreiber <arthurschreiber@github.com>

* Fix `vtexplain` to handle queries with duplicate / equivalent tuple values.

Signed-off-by: Arthur Schreiber <arthurschreiber@github.com>

Signed-off-by: Arthur Schreiber <arthurschreiber@github.com>

Signed-off-by: Arthur Schreiber <arthurschreiber@github.com>
Co-authored-by: Arthur Schreiber <arthurschreiber@github.com>
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Reviewers

@systay systay systay approved these changes

Assignees
No one assigned
Labels
Component: vtexplain changes made to vtexplain code Type: Enhancement Logical improvement (somewhere between a bug and feature)
Projects
None yet
Milestone
No milestone
Development

Successfully merging this pull request may close these issues.
3 participants
@arthurschreiber @systay @deepthi