* only copy args[0] to args[2] after fix_fields (when all item
  substitutions have already happened)

* change QT_ITEM_FUNC_NULLIF_TO_CASE (that allows to print NULLIF
  as CASE) to QT_ITEM_ORIGINAL_FUNC_NULLIF (that prohibits it).
  So that NULLIF-to-CASE is allowed by default and only disabled
  explicitly for SHOW VIEW|FUNCTION|PROCEDURE and mysql_make_view.
  By default it is allowed (in particular in error messages and
  debug output, that can happen anytime before or after optimizer).

don't do special SUM_FUNC_ITEM treatment in NULLIF for views
(as before), but do it for derived tables (when
context_analysis_only == CONTEXT_ANALYSIS_ONLY_DERIVED)

port of mysql fix WL#6098

During SST, since wsrep_sst_rsync waits for mysqld to create
"tables_flushed" file after it has successfully executed FTWRL,
it would wait forever if FTWRL fails.
Fixed by introducing a mechanism to report failure to the script.

Also, renamed wsrep_skip_append_keys to wsrep_ignore_table.
Test case : galera.galera_as_slave_gtid.test

- "Early NULLs filtering" optimization used to "peel off" Item_ref and
  Item_direct_ref wrappers from an outside column reference before
  adding "outer_table_col IS NOT NULL" into JOIN::outer_ref_cond.
- When this happened in a subquery that was evaluated in a post-GROUP-BY
  context, attempt to evaluate JOIN::outer_ref_cond would fetch an
  incorrect value of outer_table_col.

10.0 merge
10.0-galera merge
connect/10.1 merge

contains broken procedure body when used shielding quotes inside.

  If any given variable the xtrabackup-v2 sst script looks for is specified
  multiple times in cnf file then it tend to pick both of them causing
  some of the follow-up command to fail.

  Avoid this programatic mistake by honoring only the last variable assigned
  setting as done by mysqld too.

  Check https://bugs.launchpad.net/percona-xtradb-cluster/+bug/1362830

Semantics:
---------

* Generally end-user will create a separate user with needed
privileges for
    performing DONOR action.
* This user credentials are specified using wsrep_sst_auth.

* Along with this user there could be other user(s) created on the
server
    that sysadmin may use for normal or other operations
* Credentials for these user(s) can be specified in same
cluster/server
    cnf file as part of [client] section

When cluster act as DONOR and if wsrep_sst_auth is provided then it
should
strictly use it for performing SST based action.

What if end-user has same credentials for performing both SST action
and
normal admin work ?
* Then end-user can simply specify these credentials as part of
[client]
    section in cnf file and skip providing wsrep_sst_auth.

Issue:
-----

MySQL client user/password parsing preference order is as follows:
* command line (through --user/--password)
* cnf file
* MYSQL_PWD enviornment variable.

Recent change tried passing sst user password through MYSQL_PWD
(and user though --user command line param as before).

On the system where-in admin had another user for performing non-SST
actions,
credentials for such user were present in cnf file under [client]
section.

Due to mysql client preference order, SST user name was used (as it
was
passed through command line) but password of other user (meant for
non-SST)
action was being used as it was passed through cnf file.

Password passed through MYSQL_PWD was completely ignored causing
user-name/password mismatch.

Solution:
---------

* If user has specified credentials for SST then pass them through
command
    line so that they are used in priority.

(There could be security concern on passing things through command
line but
   when I tried passing user-name and password through command line to
mysql
   client and then did ps I saw this
   ./bin/mysql --user=sstuser --password=x xxxxxxxx -S /tmp/n1.sock
so seems like password is not shown)

The reason for the assertion failure is that the update statement for
the minimal row image sets only the PK column in the write_set of the
table to true. On the other hand, the trigger aims to update a different
column.

Make sure that triggers update the used columns accordingly, when being
processed.

don't transform Item_func_nullif if it's context_analysis_only

when calculating COUNT(basic_const), take into account that
this basic_const may be NULL

This fixes
MDEV-9538 Server crashes in check_show_access on SHOW STATISTICS
MDEV-9539 Server crashes in make_columns_old_format on SHOW GEOMETRY_COLUMNS
MDEV-9540 SHOW SPATIAL_REF_SYS and SHOW SYSTEM_VARIABLES return empty results with numerous warnings

when doing set_field_to_new_field (from switch_to_nullable_trigger_fields())
make sure that the field we're about to change actually belongs
to the right table (otherwise we cannot dereference new_field[]
array as the wrong table might have more fields than
new_field[] has elements)

Case: table with a NOT NULL field, BEFORE UPDATE trigger,
and UPDATE with a subquery that uses GROUP BY on that
NOT NULL field, and needs a temporary table for it.

Because of the BEFORE trigger, the field becomes nullable
temporarily. But its Item_field (used in GROUP BY) doesn't.
When working with the temptable some code looked at
item->maybe_null, some - at field->null_ptr.
The fix: make Item_field nullable when its field is.

This triggers an assert. The group key size is calculated
before the item is made nullable, so the group key doesn't
have a null byte. The fix: make fields/items nullable
before the group key size is calculated.

when replicating old temporal type fields (that don't store
metadata in the binlog), take the precision from
destination fields.

(this fixes the replication failure, crashes were
fixed in a different commit)

it's *display length* (a.k.a. field_length)
not storage length (a.k.a. pack_length)

* make a local variable for target_table->field[col]
* move an often-used bit function to my_bit.h
* remove a non-static and not really needed trivial comparison
  function with a very generic name

to avoid run-time libjemalloc.so dependency
link binary tarballs with a static libjemalloc_pic.a

- test for FLUSH TABLES hang in slave node

- avoiding the race condition, by not grabbing thd->LOCK_wsrep_thd for
  accessing thd->wsrep_exec_mode. The caller is same thread and exec mode
  can only be changed by self.

- added mtr test case for this issue
- not a perfect one, depends on some sleeps instead of checking
  if sync points are met

- added dbug sync points for further mtr test for this issue