docs(clickpipes/mysql): FAQ for binlog event exceeding max_allowed_packet#6379
Open
dtunikov wants to merge 3 commits into
Open
docs(clickpipes/mysql): FAQ for binlog event exceeding max_allowed_packet#6379dtunikov wants to merge 3 commits into
dtunikov wants to merge 3 commits into
Conversation
…d_packet Document the MySQL error 1236 "log event entry exceeded max_allowed_packet" failure mode and its mitigations: increase max_allowed_packet on the source, resync the affected table, or exclude large columns from replication. The #binlog-event-exceeded-max-allowed-packet anchor is referenced by the ClickPipes notification for the NOTIFY_BINLOG_EVENT_EXCEEDED_MAX_ALLOWED_PACKET error class. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
|
The latest updates on your projects. Learn more about Vercel for GitHub.
3 Skipped Deployments
|
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
|
|
ilidemi
reviewed
Jun 13, 2026
| ```sql | ||
| SET GLOBAL max_allowed_packet = 1073741824; -- 1 GiB | ||
| ``` | ||
| Set it in your server configuration (e.g. `my.cnf`) as well so it persists across restarts. Existing connections must be re-established for the new value to take effect. |
Member
There was a problem hiding this comment.
Suggested change
| Set it in your server configuration (e.g. `my.cnf`) as well so it persists across restarts. Existing connections must be re-established for the new value to take effect. | |
| Set it in your server configuration (e.g. `my.cnf` or the DB Parameter Group) as well so it persists across restarts. Existing connections must be re-established for the new value to take effect. |
Comment on lines
+46
to
+47
| - **If a single large row is the cause,** [resync the affected table](./table_resync.md) once `max_allowed_packet` has been increased so the pipe can move past it. | ||
| - **If you expect values larger than `1G`,** exclude the large columns from replication, as `max_allowed_packet` can't be raised beyond `1G`. See [Can I include columns I initially excluded from replication?](#include-excluded-columns). |
Member
There was a problem hiding this comment.
I don't think I thought through the task description super well. MySQL sends us the entire binlog so the customer doesn't really have a choice but resync the whole pipe. There could be nuances with determining for sure that the big row is outside of our set of tables and skipping that GTID but that hasn't come up too much yet so we don't have tooling. So for applying the value it'd just be the reconnection that happens automatically, and for >1GB we just recommend resync.
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
3 participants
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.
Context
The MySQL ClickPipe can fail with:
This happens when a single binlog event (one row change) is larger than the source server's
max_allowed_packet, aborting the binlog stream read. It's distinct from binlog corruption/purge and has its own mitigation.Change
Add a MySQL FAQ entry under
#binlog-event-exceeded-max-allowed-packetexplaining:BLOB/TEXT/JSONrows)max_allowed_packeton the source (up to1G)1GThis anchor is referenced by the new ClickPipes notification mitigation link for the
NOTIFY_BINLOG_EVENT_EXCEEDED_MAX_ALLOWED_PACKETerror class.Related
🤖 Generated with Claude Code
Note
Low Risk
Documentation-only change to the MySQL ClickPipes FAQ with no runtime or security impact.
Overview
Adds a MySQL ClickPipes FAQ section (
#binlog-event-exceeded-max-allowed-packet) for CDC failures when a binlog event exceeds the sourcemax_allowed_packet(ERROR 1236).The entry documents the cause (oversized single-row events, often large
BLOB/TEXT/JSON), how to raisemax_allowed_packeton the source (includingSET GLOBALandmy.cnf), when to resync the table after fixing a one-off large row, and when to exclude columns if values can exceed the 1G server limit—with a cross-link to the existing excluded-columns FAQ.Reviewed by Cursor Bugbot for commit 8ecfb1b. Bugbot is set up for automated code reviews on this repo. Configure here.