hang.

MDEV-22626: mysql_tzinfo_to_sql not replicates timezone to galeranodes if only 1 timezone will be loaded.

Move alter to InnoDB earlier to more correct place to handle
also if only a one timezone file is loaded.

fix_fields for the arguments of the NTH_VALUE function was updating the same reference,
so for the second argument (or after the first argument) the items were not resolved
to their corresponding field from the view as they were updating the reference to the
first argument.

depending on build config the error might be hidded,
in particular liblz4.so and libjemalloc.so make it to disappear,
but with -DWITH_INNODB_LZ4=NO -DWITH_JEMALLOC=NO it reappears.

MDEV-17066: Bytes lost or Assertion `status_var.local_memory_used == 0 after DELETE with subquery with ROLLUP

The issue here is when records are read from the temporary file
(filesort result in this case) via a cache(rr_from_cache).
The cache is initialized with init_rr_cache.
For correlated subquery the cache allocation is happening at each execution
of the subquery but the deallocation happens only once and that was
when the query execution was done.

So generally for subqueries we do two types of cleanup

1) Full cleanup: we should free all resources of the query(like temp tables).
   This is done generally when the query execution is complete or the subquery
   re-execution is not needed (case with uncorrelated subquery)

2) Partial cleanup: Minor cleanup that is required if
   the subquery needs recalculation. This is done for all the structures that
   need to be allocated for each execution (example SORT_INFO for filesort
   is allocated for each execution of the correlated subquery).

The fix here would be free the cache used by rr_from_cache in the partial
cleanup phase.

lock_rec_has_to_wait_in_queue(): Remove an obviously redundant assertion
that was added in commit a8ec4586
and also enclose a Galera-specific condition in #ifdef WITH_WSREP.

Problem:- rpl_parallel2 was failing non-deterministically
Analysis:-
When FLUSH TABLES WITH READ LOCK is executed, it will allow all worker
threads to complete their ongoing transactions and then it will pause them.
At this state FTWRL will proceed to acquire global read lock. FTWRL first
blocks threads from starting new commits, then upgrades the lock to block
commit of existing transactions.
  Step1:
    FLUSH TABLES WITH READ LOCK - Blocks new commits
  Step2:
    * STOP SLAVE command enables 'force_abort=1' which unblocks workers,
      they continue to execute events.
    * T1: Waits in 'record_gtid' call to update 'gtid_slave_pos' table with
      its current GTID, but it is blocked becuase of Step1.
    * T2: Holds COMMIT lock and waits for T1 to commit.
  Step3:
    FLUSH TABLES WITH READ LOCK - Waiting to get BLOCK_COMMIT.
This results in deadlock. When STOP SLAVE command allows paused workers to
proceed, workers should skip the execution of all further events, similar
to 'conservative' parallel mode.
Solution:-
We will assign 1 to skip_event_group when we are aborted in do_ftwrl_wait.
rpl_parallel_entry->pause_sub_id is only reset when force_abort is off in
rpl_pause_after_ftwrl.

and inaccurately

Analysis: The list of all privileges is 118 characters wide. However, the
format of error message was: "%-.32s command denied to user...". get_length()
sets the maximum width to 32 characters. As a result, only first 32
characters of list of privilege are stored.
Fix: Changing the format to "%-.100T..." so that get_length() sets width to
100. Hence, first 100 characters of the list of privilege are stored and the
type specifier 'T' appends '...' so that truncation can be seen.

Diagnostics_area::sql_errno upon query from I_S with LIMIT ROWS EXAMINED

open_normal_and_derived_table() fails because the query was already killed
as rows examined by the query are more than the limit. However, this isn't a
real error.
Fix: Check if there is actually an error before calling thd->sql_errno()
and later send a warning in handle_select() if no real error.

fixed.

lock_rec_has_to_wait
wsrep_kill_victim
lock_rec_create_low
lock_rec_add_to_queue
DeadlockChecker::select_victim()

	THD can't change from normal transaction to BF (brute force) transaction
	here, thus there is no need to syncronize access in wsrep_thd_is_BF
	function.

lock_rec_has_to_wait_in_queue

	Add condition that lock is not NULL and add assertions if we are in
	strong state.

/home/buildbot/buildbot/build/storage/xtradb/mtr/mtr0mtr.cc:97:37: error: invalid access to non-static data member ‘fil_space_t::latch’  of NULL object [-Werror=invalid-offsetof]

Make sure system tables aren't open, as the test kills the server

- Adding lock_wait_timeout value as 1 make sure that truncate table
fails instead of making MDL timeout.

The purpose of the InnoDB doublewrite buffer is to make InnoDB
tolerant against cases where the server was killed in the middle
of a page write. (In Linux, killing a process may interrupt a
write system call, typically on a 4096-byte boundary.)

There may exist multiple copies of a page number in the doublewrite
buffer. Recovery should choose the latest valid copy of the page.
By design, the FIL_PAGE_LSN must not precede the latest checkpoint LSN
nor be later than the end of the recovered log.

For page_compressed and encrypted pages, we were missing proper
consistency checks. In the 10.4 data set generated for in MDEV-23231,
the data file contained a valid page_compressed page, and an
identical copy of that page was also present in the doublewrite
buffer. But, recovery would incorrectly consider the page invalid
and restore an uncompressed copy of the same page that had been
written before the log checkpoint. (In fact, no redo log was to
be applied to that page.)

buf_dblwr_process(): Validate the FIL_PAGE_LSN in the doublewrite
buffer pages, and always skip page 0, because those pages should
have been recovered by Datafile::restore_from_doublewrite() if
necessary.

Datafile::restore_from_doublewrite(): Choose the latest applicable
page from the doublewrite buffer.

recv_dblwr_t::find_page(): Also validate encrypted or
page_compressed pages.

recv_dblwr_t::validate_page(): New function to validate a page,
either a copy in a data file or in the doublewrite buffer.
Also validate encrypted or page_compressed pages.

This is joint work with Thirunarayanan Balathandayuthapani.

row_vers_impl_x_locked_low(): clust_offsets may point to memory
that is allocated by mem_heap_alloc() and may have been freed.
For initializing clust_offsets, try to use the stack-allocated
buffer instead of a pointer that may point to freed memory.

This fixes a regression that was introduced in
commit f0aa073f (MDEV-20950).

MDEV-18042 Server crashes upon adding a non-null date column under NO_ZERO_DATE with ALGORITHM=INPLACE

accept table_name and db_name instead of table_share in make_truncated_value_warning

Call mark_columns_per_binlog_row_image before find_row() to set up table->vcol_set early,
so the virtual column value will be updated after record read (ha_rnd_pos/ha_index_next/etc)
by table->update_virtual_fields() call

MDEV-22521 Server crashes in traverse_role_graph_up or Assertion `user' fails in traverse_role_graph_impl

Problem:
========
In row_merge_drop_indexes(), InnoDB drops only the index from
dictionary and frees the index pages but it maintains the index
object if the table is being used by other DML threads. It sets
the online status of the index to ONLINE_INDEX_ABORTED_DROPPED.
Removing the index from dictionary doesn't remove the
corressponding ahi entries of the index. When block is being
reused, InnoDB tries to remove ahi entries for the block and
it fails if index online status is ONLINE_INDEX_ABORTED_DROPPED.

Fix:
====
MDEV-22456 allows the index ahi entries to be dropped lazily.
so checking online status in btr_search_drop_page_hash_index()
is meaningless and should be removed.

The only change between Percona XtraDB Server 5.6.48-88.0
and 5.6.49-89.0 (apart from the version number change) was
percona/percona-server@25ec24092064c2ab95752705e592e0c038ec1111
which we had already addressed in
commit 7c03edf2 and
commit c0fca286.

trx_rollback_active(), trx_rollback_resurrected(): Replace
an incorrect condition that we failed to replace in
commit b68f1d84 (MDEV-21217).

Do not collect EITS statistics for this statement:

  ALTER TABLE t ANALYZE PARTITION p

EITS stats are currently global, not per-partition.
Collecting global stats when we are asked to process just one partition
causes issues for DBAs.

MDEV-23010 UPDATE privilege at Database and Table level fail to update with SELECT command denied to user

check both column- and table-level grants when looking for SELECT
privilege on UPDATE statement.