mysql-test/t/features.test:
  --ps-protocol counts both prepare and execute
mysql-test/t/last_value.test:
  Disable ps-protocol for metadata tests

- Performed some refactoring and simplification that was enabled and required by the merge.

Analysis:
The queries in question use the [unique | index]_subquery execution methods.
These methods reuse the ref keys constructed by create_ref_for_key(). The
way create_ref_for_key() works is that it doesn't store in ref.key_copy[]
store_key elements that represent constants. In particular it doesn't store
the store_key for NULL constants.

The execution of [unique | index]_subquery calls
subselect_uniquesubquery_engine::copy_ref_key, which in addition to copy
the left IN argument into a index lookup key, is supposed to detect if
the left IN argument contains NULLs. Since the store_key for the NULL
constant is not copied into the key array, the null is not detected, and
execution erroneously proceeds as if it should look for a complete match.

Solution:
The solution (unlike MySQL) is to reuse already computed information about
NULL presence. Item_in_optimizer::val_int already finds out if the left IN
operand contains NULLs. The fix propagates this to the execution methods
subselect_[unique | index]subquery_engine::exec so it knows if there were
NULL values independent of the presence of keys.

In addition the patch siplifies copy_ref_key() and the logic that hanldes
the case of NULLs in the left IN operand.

mysql-test/include/index_merge2.inc:
  InnoDB did report 9 or 7 rows in explain

mysql-test/suite/heap/heap_hash.result:
  Added test case
mysql-test/suite/heap/heap_hash.test:
  Added test case
storage/heap/hp_hash.c:
  Limit key data length to max key length

feature_dynamic_columns,feature_fulltext,feature_gis,feature_locale,feature_subquery,feature_timezone,feature_trigger,feature_xml
Opened_views, Executed_triggers, Executed_events
Added new process status 'updating status' as part of 'freeing items'

mysql-test/r/features.result:
  Test of feature_xxx status variables
mysql-test/r/mysqld--help.result:
  Removed duplicated 'language' variable.
mysql-test/r/view.result:
  Test of opened_views
mysql-test/suite/rpl/t/rpl_start_stop_slave.test:
  Write more information on failure
mysql-test/t/features.test:
  Test of feature_xxx status variables
mysql-test/t/view.test:
  Test of opened_views
sql/event_scheduler.cc:
  Increment executed_events status variable
sql/field.cc:
  Increment status variable
sql/item_func.cc:
  Increment status variable
sql/item_strfunc.cc:
  Increment status variable
sql/item_subselect.cc:
  Increment status variable
sql/item_xmlfunc.cc:
  Increment status variable
sql/mysqld.cc:
  Add new status variables to 'show status'
sql/mysqld.h:
  Added executed_events
sql/sql_base.cc:
  Increment status variable
sql/sql_class.h:
  Add new status variables
sql/sql_parse.cc:
  Added new process status 'updating status' as part of 'freeing items'
sql/sql_trigger.cc:
  Increment status variable
sql/sys_vars.cc:
  Increment status variable
sql/tztime.cc:
  Increment status variable

Simplify code

sql/derror.cc:
  Better error message
sql/mysqld.cc:
  Simplify usage of lc_messages_dir_ptr.
  Don't give warnings that --log-bin should be used if --log-bin or --skip-log-bin is used.

As far as we reopen tables so TABLE become invalid we should remove the pointer on cleanup().

As far as we reopen tables so TABLE become invalid we should remove the pointer on cleanup().

The DELETE for emplicitly emptied MEMORY tables should be written directly to binlog.

Link view/derived table fields to a real table to check turning the table record to null row.

Item_direct_view_ref wrapper now checks if table is turned to null row.

Added function last_value() which returns the last value but evalutes all arguments as a side effect.
Original patch by Eric Herman

client/mysql.cc:
  Added LAST_VALUE
mysql-test/r/last_value.result:
  Testing of LAST_VALUE
mysql-test/t/last_value.test:
  Testing of LAST_VALUE
sql/item_func.cc:
  Added LAST_VALUE()
sql/item_func.h:
  Added LAST_VALUE()
sql/lex.h:
  Added LAST_VALUE()
sql/sql_yacc.yy:
  Added LAST_VALUE()

MDEV-481 Assertion `pins->pin[i] == 0' failed in _lf_pinbox_put_pins on concurrent OPTIMIZE TABLE and DML with Aria tables

A bug in the lock-free hash implementation!
when lsearch() has not found the key, the caller needs to unpin all the three pins,
because lsearch() was using all the three.

   not every time.
2. Increase purgatory size.

include/lf.h:
  allocate larger purgatory
mysys/lf_alloc-pin.c:
  typo.

        Autointersections of an object were treated as nodes, so the wrong result.

per-file comments:
  mysql-test/r/gis.result
Bug #1043845 st_distance() results are incorrect depending on variable order.
        test result updated.
  mysql-test/t/gis.test
Bug #1043845 st_distance() results are incorrect depending on variable order.
        test case added.
  sql/item.cc
        small fix to make compilers happy.
  sql/item_geofunc.cc
Bug #1043845 st_distance() results are incorrect depending on variable order.
        Skip intersection points when calculate distance.

MDEV-414 Depending on indexes or execution plans, a warning on incorrect or out of range values in WHERE condition is sometimes produced and sometimes not

use the same method that disables warnings in all relevant places, remove redundant function

When we append data to the binlog file, we use fdatasync() to ensure
the data gets to disk so that crash recovery can work.

Unfortunately there seems to be a bug in ext3/ext4 on linux, so that
fdatasync() does not correctly sync all data when the size of a file
is increased. This causes crash recovery to not work correctly (it
loses transactions from the binlog).

As a work-around, use fsync() for the binlog, not fdatasync(). Since
we are increasing the file size, (correct) fdatasync() will most
likely not be faster than fsync() on any file system, and fsync()
does work correctly on ext3/ext4. This avoids the need to try to
detect if we are running on buggy ext3/ext4.

store the precision in uint, not uint8

MDEV-438 Microseconds: Precision is ignored in CURRENT_TIMESTAMP(N) when it is given as a default column value

The syntax for specifying precision in the DEFAULT clause is unintentional and unsupported.
Don't allow it anymore.

1. Field_newdate::get_date should refuse to return a date with zeros when
   TIME_NO_ZERO_IN_DATE is set, not when TIME_FUZZY_DATE is unset
2. Item_func_to_days and Item_date_add_interval can only work with valid dates,
   no zeros allowed.

fix Item_func_add_time::get_date() to generate valid dates.
Move the validity check inside get_date_from_daynr()
instead of relying on callers
(5 that had it, and 2 that did not, but should've)

Split ER_NO_SUCH_TABLE into ER_NO_SUCH_TABLE and ER_NO_SUCH_TABLE_IN_ENGINE to be able to distingus if a .frm file is missing or if the table is missing in the engine.


sql/handler.cc:
  Added ER_NO_SUCH_TABLE_IN_ENGINE
sql/rpl_record.cc:
  Fixed wrong printf
sql/share/errmsg-utf8.txt:
  Added ER_NO_SUCH_TABLE_IN_ENGINE
sql/sp.cc:
  Added ER_NO_SUCH_TABLE_IN_ENGINE
sql/sp_head.cc:
  Added ER_NO_SUCH_TABLE_IN_ENGINE
sql/sql_admin.cc:
  Added ER_NO_SUCH_TABLE_IN_ENGINE
sql/sql_base.cc:
  Added ER_NO_SUCH_TABLE_IN_ENGINE
sql/sql_show.cc:
  Added ER_NO_SUCH_TABLE_IN_ENGINE
sql/table.cc:
  Fixed typo

MDEV-405: Server crashes in test_if_skip_sort_order on EXPLAIN with GROUP BY and HAVING in EXISTS subquery
- Testcase