fix virtual column not found when remote read happens (#9920)#9928
Merged
ti-chi-bot[bot] merged 2 commits intopingcap:release-8.5from Feb 28, 2025
Merged
Conversation
Signed-off-by: ti-chi-bot <ti-community-prow-bot@tidb.io>
12 tasks
Member
Author
|
@guo-shaoge This PR has conflicts, I have hold it. |
Signed-off-by: guo-shaoge <shaoge1994@163.com>
solotzg
approved these changes
Feb 27, 2025
Contributor
|
[APPROVALNOTIFIER] This PR is APPROVED This pull-request has been approved by: solotzg, windtalker The full list of commands accepted by this bot can be found here. The pull request process is described here DetailsNeeds approval from an approver in each of these files:
Approvers can indicate their approval by writing |
Contributor
[LGTM Timeline notifier]Timeline:
|
yongman
pushed a commit
to yongman/tiflash
that referenced
this pull request
Jun 18, 2025
…ingcap#9928) close pingcap#9561 Signed-off-by: ti-chi-bot <ti-community-prow-bot@tidb.io> Signed-off-by: guo-shaoge <shaoge1994@163.com> Co-authored-by: guo-shaoge <shaoge1994@163.com>
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
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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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.
This is an automated cherry-pick of #9920
What problem does this PR solve?
Issue Number: close #9561
Problem Summary:
gen_col is a virtual generated column. The current approach is that TiFlash generates an empty column and places it in the block. Then, it passes the block to TiDB, allowing TiDB to calculate and populate the column.
I’ve named this column generated_xxx.
The information about this column is marked in tipb_table_scan.columns with a flag. When TiFlash sees this flag, it automatically adds a generated_xxx column.
However, this situation has an issue when a remote read occurs: the block returned from the remote read, when parsed, assigns names to each column based on RemoteRequest.schema. For example, if TiFlash-1 receives a block from TiFlash-2, it will parse it as <col, gen_col>.
But TiFlash-1, in the table scan's projection, expects the block to be <col, generated_xxx>. So, when projecting the block from the remote read, an error occurs because it cannot find the generated_xxx column.
What is changed and how it works?
make the column name of local read and remote read be same
Check List
Tests
Side effects
Documentation
Release note