If it is not enabled, build wsrep as static "stub" library from wsrep_dummy.cc
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Allow static plugins to export symbols (on Unix)
wsrep_info relies on wsrep defined symbols (e.g LOCK_wsrep_config_state)
exported from mysqld
The previous threads locked need to be released too.
This occurs if the initialization of any of the non-first
mutex/conditition variables errors occurs.
When transaction creates or drops temporary tables and afterward its statement
faces an error even the transactional table statement's cached ROW
format events get involved into binlog and are visible after the transaction's commit.
Fixed with proper analysis of whether the errored-out statement needs
to be rolled back in binlog.
For instance a fact of already cached CREATE or DROP for temporary
tables by previous statements alone
does not cause to retain the being errored-out statement events in the
cache.
Conversely, if the statement creates or drops a temporary table
itself it can't be rolled back - this rule remains.
versioning_fields flag indicates that any columns were specified WITH
SYSTEM VERSIONING. In that case we imply WITH SYSTEM VERSIONING for
the whole table and WITHOUT SYSTEM VERSIONING for the other columns.
When restoring lastinx last_key.keyinfo must be updated as well. The
good example is in _ma_check_index().
The point of failure is extra(HA_EXTRA_NO_KEYREAD) in
ha_maria::get_auto_increment():
1. extra(HA_EXTRA_KEYREAD) saves lastinx;
2. maria_rkey() changes index, so the lastinx and last_key.keyinfo;
3. extra(HA_EXTRA_NO_KEYREAD) restores lastinx but not
last_key.keyinfo.
So we have discrepancy between lastinx and last_key.keyinfo after 3.
my_copy_fix_mb() passed MIN(src_length,dst_length) to
my_append_fix_badly_formed_tail(). It could break a multi-byte
character in the middle, which put the question mark to the
destination.
Fixing the code to pass the true src_length to
my_append_fix_badly_formed_tail().
Replaced HA_ADMIN_NOT_IMPLEMENTED error code by HA_ADMIN_OK. Now CHECK
TABLE does not fail by unsupported check_misplaced_rows(). Admin
message is not needed as well.
Test case is the same as for MDEV-21011 (a7cf0db3d8), the result have
been changed.
There is a case when implicit primary key may be changed when removing
NOT NULL from the part of unique key. In that case we update
modified_primary_key which is then used to not skip key sorting.
According to is_candidate_key() there is no other cases when primary
kay may be changed implicitly.
mysql_prepare_create_table() does my_qsort(sort_keys) on key
info. This sorting is indeterministic: a table is created with one
order and inplace alter may overwrite frm with another order. Since
inplace alter does nothing about key info for MyISAM/Aria storage
engines this results in discrepancy between frm and storage engine key
definitions.
The fix avoids the sorting of keys when no new keys added by ALTER
(and this is ok for MyISAM/Aria since it cannot add new keys inplace).
Notes:
mi_keydef_write()/mi_keyseg_write() are used only in mi_create(). They
should be used in ha_inplace_alter_table() as well.
Aria corruption detection is unimplemented: maria_check_definition()
is never used!
MySQL 8.0 has this bug as well as of 8.0.26.
This breaks main.long_unique in 10.4. The new result is correct and
should be applied as it just different (original) order of keys.
There is a server startup option --gdb a.k.a. --debug-gdb that requests
signals to be set for more convenient debugging. Most notably, SIGINT
(ctrl-c) will not be ignored, and you will be able to interrupt the
execution of the server while GDB is attached to it.
When we are debugging, the signal handlers that would normally display
a terse stack trace are useless.
When we are debugging with rr, the signal handlers may interfere with
a SIGKILL that could be sent to the process by the environment, and ruin
the rr replay trace, due to a Linux kernel bug
https://lkml.org/lkml/2021/10/31/311
To be able to diagnose bugs in kill+restart tests, we may really need
both a trace before the SIGKILL and a trace of the failure after a
subsequent server startup. So, we had better avoid hitting the problem
by simply not installing those signal handlers.
