This repository has been archived by the owner on Oct 18, 2023. It is now read-only.
bottomless: don't ever restore if WAL file exists #733
Conversation
This file contains 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
psarna
suggested changes
Oct 5, 2023
| self.reset_frames(wal_pages + 1); | ||
| Ok(Some(RestoreAction::ReuseGeneration(generation))) | ||
| } else { | ||
| // db file is empty, but WAL exists. Calling for new snapshot. |
There was a problem hiding this comment.
I think this is incorrect. An empty db with pragma journal_mode=wal in practice always has a change counter >= 1. If we detect 0 here, it means we have an empty/incorrect file, which also means we don't have any metadata necessary to decide what to restore from this WAL file. From consistency point of view, it's best to error out here and require manual intervention to see what's in the WAL file and why it was left here even though we don't have a valid main db file.
Sign up for free
to subscribe to this conversation on GitHub.
Already have an account?
Sign in.
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Outdated suggestions cannot be applied.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.
In the latest changes we decided not to restore if a non-empty db file was found. Additionally we expand it if a non-empty WAL exists (even if db file was was none or empty).