Cause: a copy of the joined TABLE_LIST is created during multi_update::prepare
and TABLE::pos_in_table_list of the tables are set to point to the new
TABLE_LIST object. This prevents some optimization steps to perform correctly.
Solution: do not update pos_in_table_list during multi_update::prepare

MDEV-14642 Assertion 'table->s->db_create_options == part_table->s->db_create_options' failed in compare_table_with_partition

When trying to execute ALTER TABLE EXCHANGE PARTITION with different
definitions, assertion

    table->s->db_create_options == part_table->s->db_create_options

failed in compare_table_with_partition().

However, this execution should not be allowed since executing
'exchange partition' requires the identical structure of the two tables.

To fix the problem, I deleted the assertion code and added code that
returns an error that indicates tables have different definitions.

Reviewed By: Nayuta Yanagisawa

The counter srv_stats.key_rotation_list_length is never updated, and
therefore Innodb_encryption_key_rotation_list_length will always be 0.

The view INFORMATION_SCHEMA.INNODB_TABLESPACES_ENCRYPTION comes close
to reporting this information.

The counters were added in commit 5e55d1ce
and any code to update them was
inadvertently removed in commit 2e814d47
when applying InnoDB changes from MySQL 5.7.

Let us remove these counters that never reported anything useful. If such
statistics are really needed in a special case, they can be obtained by
instrumenting the code by some means, such as eBPF or a source code patch.

- In best_extension_by_limited_search(), do not check for
  "(remaining_tables & real_table_bit)", it is guaranteed to be true.
  Make it an assert.
- In (!idx || check_interleaving_with_nj())", remove the !idx part.
  This check made sense only in the original version of this function.
- "micro optimization" in check_interleaving_with_nj().

The condition of the if statements are always true.

Reviewed-by: Jan Lindström <jan.lindstrom@mariadb.com>

Make sure that nodes have correct auto_increment_offset when
they start and when control is turned on.

Fixed failing main.default on Windows
(to trigger an assert the test needed a debug build without
safemalloc, as 0xa5 happened to have the important bit set "correctly")

Test compat/oracle.sp-package-mysqldump needed re-record.

MDEV-21810 MBR: Unexpected "Unsafe statement" warning for unsafe IODKU

MDEV-17614 fixes to replication unsafety for INSERT ON DUP KEY UPDATE
on two or more unique key table left a flaw. The fixes checked the
safety condition per each inserted record with the idea to catch a user-created
value to an autoincrement column and when that succeeds the autoincrement column
would become the source of unsafety too.
It was not expected that after a duplicate error the next record's
write_set may become different and the unsafe decision for that
specific record will be computed to screw the Query's binlogging
state and when @@binlog_format is MIXED nothing gets bin-logged.

This case has been already fixed in 10.5.2 by 91ab42a8 that
relocated/optimized THD::decide_logging_format_low() out of the record insert
loop. The safety decision is computed once and at the right time.
Pertinent parts of the commit are cherry-picked.

Also a spurious warning about unsafety is removed when MIXED
@@binlog_format; original MDEV-17614 test result corrected.
The original test of MDEV-17614 is extended and made more readable.

or slow query log when the log_output=TABLE.

When this happens, we temporary disable by changing log_output until
we've created the general_log and slow_log tables again.

Move </database> in xml mode until after the transaction_registry.

General_log and slow_log tables where moved to be first to be dumped so
that the disabling of the general/slow queries is minimal.

Previously the correct SQL mode for a stored routine or
package was only set before doing the CREATE part, this
worked out for PROCEDUREs and FUNCTIONs, but with ORACLE
mode specific PACKAGEs the DROP also only works in ORACLE
mode.

Moving the setting of the sql_mode a few lines up to happen
right before the DROP statement is writen fixes this.

MDEV-28402 ASAN heap-use-after-free in create_tmp_table, Assertion `l_offset >= 0 && table->s->rec_buff_length - l_offset > 0'

Make default() function follow Item_field and use get_tmp_table_item() for
change_to_use_tmp_fields().

row_ins_sec_index_entry_low(): If a separate mini-transaction is
needed to adjust the minimum bounding rectangle (MBR) in the parent
page, we must disable redo logging if the table is a temporary table.
For temporary tables, no log is supposed to be written, because
the temporary tablespace will be reinitialized on server restart.

rtr_update_mbr_field(): Plug a memory leak.

In SELECT_LEX::update_used_tables(),
do not run the loop setting tl->table->maybe_null
when tl is an eliminated table

(Rationale: First, with current table elimination, tl already
 has maybe_null=1. Second, one should not care what flags
 eliminated tables had)

(This is the assert that was added in fix for MDEV-26047)

Table elimination may remove an ON expression from an outer join.
However SELECT_LEX::update_used_tables() will still call

  item->walk(&Item::eval_not_null_tables)

for eliminated expressions. If the subquery is constant and cheap
Item_cond_and will attempt to evaluate it, which will trigger an
assert.
The fix is not to call update_used_tables() or eval_not_null_tables()
for ON expressions that were eliminated.

As Travis is not used anymore for CI is not wise to keep untested CI files laying around
that someone can base their effort to update un-used files.

Debian script debian-start upgrades database (which can be huge)
and prints lots of unnecessary information (not errors). Add
'--silent' to only sport possible errors

* FreeBSD returns errno 31 (EMLINK, Too many links),
  not 40 (ELOOP, Too many levels of symbolic links)
* (`mysqlbinlog|mysql`) was just crazy, why did it ever work?
* socket_ipv6.inc check (that checked whether ipv6 is supported)
  only worked correctly when ipv6 was supported
* perfschema.socket_summary_by_instance was changing global variables
  and then skip-ing the test (because on missing ipv6)

Window Functions code tries to minimize the number of times it
needs to sort the select's resultset by finding "compatible"
OVER (PARTITION BY ... ORDER BY ...) clauses.

This employs compare_order_elements(). That function assumed that
the order expressions are Item_field-derived objects (that refer
to a temp.table). But this is not always the case: one can
construct queries order expressions are arbitrary item expressions.

Add handling for such expressions: sort them according to the window
specification they appeared in.
This means we cannot detect that two compatible PARTITION BY clauses
that use expressions can share the sorting step.
But at least we won't crash.

MDEV-17843 Assertion `page_rec_is_leaf(rec)' failed in lock_rec_queue_validate upon SHOW ENGINE INNODB STATUS

lock_validate() accumulates page ids under locked lock_sys->mutex, then
releases the latch, and invokes lock_rec_block_validate() for each page.
Some other thread has ability to add/remove locks and change pages
between releasing the latch in lock_validate() and acquiring it in
lock_rec_validate_page().

lock_rec_validate_page() can invoke lock_rec_queue_validate() for
non-locked supremum, what can cause ut_ad(page_rec_is_leaf(rec)) failure
in lock_rec_queue_validate().

The fix is to invoke lock_rec_queue_validate() only for locked records
in lock_rec_validate_page().

The error message in lock_rec_block_validate() is not necessary as
BUF_GET_POSSIBLY_FREED mode is used to get block from buffer pool, and
this is not error if a block was evicted.

The test case would require new debug sync point. I think it's not
necessary as the fixed code is debug-only.

    Problem:
    ==============
    By testing `pgrep` with `--ns` option,
    introduced with MDEV-21331, commit fb7c1b94,
    I noted that:
    a) `--ns`  cannot use more than single PID.
    b) `--ns` is returning the processes of the namespace to which supplied PID belongs to.
    So by that sense command `pgrep -x --ns $$ mysqld` will always return an error and skip
    checking of the existing PID of the server.

    Solution:
    ==============
    Suggested solution is to add `--nslist pid`, since `--ns` needs to know in which namespace type it should look for.
    See `pgrep --help` for different namespace types.
    Note also that this works *only* if script is run as a `root` (we have that case here).

    Current PR is a part of:
    1. MDEV-21331: sync preinst and postrm script
    2. MDEV-15718: check for exact mysqld process

    This commit:
    a) fixes fb7c1b94
    b) Closes PR #2068 (obsolete)
    c) Closes PR #2069 (obsolete)

    Thanks Faustin Lammler <faustin@mariadb.org> for testing and verifying
    Reviewed by <>

MDEV-28446 mariabackup prepare fails for incrementals if a new schema is created after full backup is taken

When "mariabackup --target-dir=$basedir --incremental-dir=$incremental_dir"
is running and is moving a new table file (e.g. `db1/t1.new`) from the
incremental directory to the base directory, it needs to verify that the base
backup database directory (e.g. `$basedir/db1`) really exists
(or create it otherwise).

The table `db1/t1` can come from a new database `db1` which
was created during the base mariabackup execution time.

In such case the directory `db1` exists only in the incremental directory,
but does not exist in the base directory.

Moved LIMIT warning from vers_set_hist_part() to new call
vers_check_limit() at table unlock phase. At that point
read_partitions bitmap is already pruned by DML code (see
prune_partitions(), find_used_partitions()) so we have to set
corresponding bits for working history partition.

Also we don't do my_error(ME_WARNING|ME_ERROR_LOG), because at that
point it doesn't update warnings number, so command reports 0 warnings
(but warning list is still updated). Instead we do
push_warning_printf() and sql_print_warning() separately.

Under LOCK TABLES external_lock(F_UNLCK) is not executed. There is
start_stmt(), but no corresponding "stop_stmt()". So for that mode we
call vers_check_limit() directly from close_thread_tables().

Test result has been changed according to new LIMIT and warning
printing algorithm. For convenience all LIMIT warnings are marked with
"You see warning above ^".

TODO MDEV-20345 fixed. Now vers_history_generating() contains
fine-grained list of DML-commands that can generate history (and TODO
mechanism worked well).

Like in MDEV-27217 vers_set_hist_part() for LIMIT depends on all
partitions selected in read_partitions. That bugfix just disabled
partition selection for DELETE with this check:

  if (table->pos_in_table_list &&
      table->pos_in_table_list->partition_names)
  {
    return HA_ERR_PARTITION_LIST;
  }

ALTER TABLE TRUNCATE PARTITION is a different story. First, it doesn't
update pos_in_table_list->partition_names, but
thd->lex->alter_info.partition_names. But we cannot depend on that
since alter_info will be stale for DML. Second, we should not disable
TRUNCATE PARTITION for that to be consistent with TRUNCATE TABLE
behavior.

Now we don't do vers_set_hist_part() for ALTER TABLE as this command
is not DML, so it does not produce history.

test case only

it was showing ca and capath instead of crl and crl_path

Expression_cache_tmptable object uses an Expression_cache_tracker object
to report the statistics.

In the common scenario, Expression_cache_tmptable destructor sets
tracker->cache=NULL. The tracker object survives after the expression
cache is deleted and one may call cache_tracker->fetch_current_stats()
for it with no harm.

However a degenerate cache with no parameters does not set
tracker->cache=NULL in Expression_cache_tmptable destructor which
results in an attempt to use freed data in the
cache_tracker->fetch_current_stats() call.

Fixed by setting tracker->cache to NULL and wrapping the assignment into
a function.

Few initializations to the connection_info structure added.
I think they can be removed if we are sure the bug was fixed.

btr_insert_into_right_sibling(): Inherit any gap lock from the
left sibling to the right sibling before inserting the record
to the right sibling and updating the node pointer(s).

lock_update_node_pointer(): Update locks in case a node pointer
will move.

Based on mysql/mysql-server@c7d93c274fdc5c56e36458fa4000fa3a483ffffd

ha_innobase::get_auto_increment(): In the overflow check, account
for 64-bit unsigned integer wrap-around.

Based on mysql/mysql-server@25ecfe7f49b5a649e96d462cb90602de9de3b919