[girihimanshu540-prog]

#Jira: https://mariadb.org
Fixes: MDEV-41989

Description

Fixes a duplicate key handling regression where a cross-partition row update incorrectly returns ERROR 1022 (Can't write; duplicate key in table) instead of the expected ERROR 1062 (Duplicate entry...).

Fix

Introduced a variable saved_last_part to preserve the initial m_last_part context prior to updating the bulk insert partition state. If ha_update_row() encounters a failure within the cross-partition routine, the initial state is restored to ensure the error subsystem correctly references the expected table handler, properly returning ER_DUP_ENTRY.

[CLAassistant]

All committers have signed the CLA.

[gkodinov]

Thank you for your contribution! This is a preliminary review.

Couple of things to fix:

1. Please keep just one commit: fwiw, github can do merges with rebase. Please use that
2. Please add a commit message to your commit
3. We fix errors in the lowest affected version. In this case I'd suggest 11.4 since this is just a readability improvement and not something so critical that it'd warrant a fix in 10.11 (IMHO).
4. the issues mentioned below: buildbot must be clean.

[gkodinov]

move this to the top of the function to fix the following compile error:

/home/buildbot/aarch64-debian-12/build/sql/ha_partition.cc: In member function ‘virtual int ha_partition::update_row(const uchar*, const uchar*)’:
/home/buildbot/aarch64-debian-12/build/sql/ha_partition.cc:4759:1: error: jump to label ‘exit’
 4759 | exit:
      | ^~~~
/home/buildbot/aarch64-debian-12/build/sql/ha_partition.cc:4716:10: note:   from here
 4716 |     goto exit;
      |          ^~~~
/home/buildbot/aarch64-debian-12/build/sql/ha_partition.cc:4719:10: note:   crosses initialization of ‘uint32 saved_last_part’
 4719 |   uint32 saved_last_part= m_last_part;
      |          ^~~~~~~~~~~~~~~
/home/buildbot/aarch64-debian-12/build/sql/ha_partition.cc:4759:1: error: jump to label ‘exit’
 4759 | exit:
      | ^~~~
/home/buildbot/aarch64-debian-12/build/sql/ha_partition.cc:4712:10: note:   from here
 4712 |     goto exit;
      |          ^~~~
/home/buildbot/aarch64-debian-12/build/sql/ha_partition.cc:4719:10: note:   crosses initialization of ‘uint32 saved_last_part’
 4719 |   uint32 saved_last_part= m_last_part;
      |          ^~~~~~~~~~~~~~~
make[2]: *** [sql/CMakeFiles/partition.dir/build.make:76: sql/CMakeFiles/partition.dir/ha_partition.cc.o] Error 1
make[1]: *** [CMakeFiles/Makefile2:11024: sql/CMakeFiles/partition.dir/all] Error 2
make[1]: *** Waiting for unfinished jobs....

[gkodinov]

Move this test into the relevant partitioning suite and pick a file to put it in that's testing similar things.
Or keep it in a separate file, but prefix it with

--echo # 
--echo # MDEV-41989: Fix duplicate key error code on cross-partition update - #6049
--echo #

And suffix it with

--echo End of 11.4 tests

Also, make sure to use the following at the top (as the rest of the part suite files do):

# The server must support partitioning.
--source include/have_partition.inc