Fixed the handling of system variable retrieval
in prepared statements : added a cleanup method
that clears up the cache and restores the 
original scope of the variable (which is overwritten
at fix_fields()).

TRIGGERS.SQL_MODE, EVENTS.SQL_MODE, TRIGGERS.DEFINER:
field type is changed to VARCHAR.

The problem was that PACK_KEYS and MAX_ROWS clause in ALTER TABLE did not trigger
table reconstruction.
The fix is to rebuild a table if PACK_KEYS or MAX_ROWS are specified.

Hide "Table doesn't exist" errors if the table belongs to a merge table.

The problem: table_open_method is not calculated properly if '*' is used in 'select'
The fix: added table_open_method calculation for such case

                  
The code to get read the value of a system variable was extracting its value 
on PREPARE stage and was substituting the value (as a constant) into the parse tree.
Note that this must be a reversible transformation, i.e. it must be reversed before
each re-execution.
Unfortunately this cannot be reliably done using the current code, because there are
other non-reversible source tree transformations that can interfere with this
reversible transformation.
Fixed by not resolving the value at PREPARE, but at EXECUTE (as the rest of the 
functions operate). Added a cache of the value (so that it's constant throughout
the execution of the query). Note that the cache also caches NULL values.
Updated an obsolete related test suite (variables-big) and the code to test the 
result type of system variables (as per bug 74).

ha_statistic_increment for rpl_temporary

Problem: in some cases master send a special event to reconnecting
slave to keep slave's temporary tables (see #17284) and they still 
have references to the "old" SQL slave thread and use them to access
thread's data.

Fix: set temporary tables thread references to the actual SQL slave
thread in such cases.

warnings)

Before this fix, several places in the code would raise a warning with an
error code 0, making it impossible for a stored procedure, a connector,
or a client application to trigger logic to handle the warning.
Also, the warning text was hard coded, and therefore not translated.

With this fix, new errors numbers have been created to represent these
warnings, and the warning text is coded in the errmsg.txt file.

so that if the substitution contains single-quotes, the program will fail.

Adds --general-log-file, --slow-query-log-file command-
line options to match system variables of the same names.

Deprecates --log, --log-slow-queries command-line option
and log, log_slow_queries system-variables for v7.0; they
are superseded by general_log/general_log_file and
slow_query_log/slow_query_log_file, respectively.

"Trigger fired multiple times leads to gaps in auto_increment sequence".
The bug was that if a trigger fired multiple times inside a top
statement (for example top-statement is a multi-row INSERT,
and trigger is ON INSERT), and that trigger inserted into an auto_increment
column, then gaps could be observed in the auto_increment sequence,
even if there were no other users of the database (no concurrency).
It was wrong usage of THD::auto_inc_intervals_in_cur_stmt_for_binlog.
Note that the fix changes "class handler", I'll tell the Storage Engine API team.

MyISAM blocks index usage for bulk insert into zero-records tables.
See ha_myisam::start_bulk_insert() lines from
...
    if (file->state->records == 0 ...
...

That causes problems for partition engine when some partitions have records some not
as the engine uses same access method for all partitions.

Now partition engine doesn't call index_first/index_last
for empty tables.

per-file comments:
  mysql-test/r/partition.result
        Bug#38005 Partitions: error with insert select.
        test result

  mysql-test/t/partition.test
        Bug#38005 Partitions: error with insert select.
        test case

  sql/ha_partition.cc
        Bug#38005 Partitions: error with insert select.
        ha_engine::index_first and
        ha_engine::index_last not called for empty tables.

Adds --general_log_file, --slow_query_log_file command-
line options to match system variables of the same names.

Deprecates --log, --log-slow-queries command-line options
and log, log_slow_queries system-variables for v7.0; they
are superseded by general_log/general_log_file and
slow_query_log/slow_query_log_file, respectively.

      
    problems are located in the sql_partition.cc where functions calculation
    partition_id don't expect error returned from item->val_int().
    Fixed by adding checks to these functions.
    Note  - it tries to fix more problems than just the reported bug.
      
per-file comments:
modified:
  mysql-test/r/partition.result
    Bug#38083 Error-causing row inserted into partitioned table despite error
        test result
  mysql-test/t/partition.test
    Bug#38083 Error-causing row inserted into partitioned table despite error
        test case
  sql/opt_range.cc
    Bug#38083 Error-causing row inserted into partitioned table despite error
        get_part_id() call fixed
  sql/partition_info.h
    Bug#38083 Error-causing row inserted into partitioned table despite error
        get_subpart_id_func interface changed. 
  sql/sql_partition.cc
    Bug#38083 Error-causing row inserted into partitioned table despite error
        various functions calculationg partition_id and subpart_id didn't expect
            an error returned from item->val_int().  Error checks added.

with actual tree

(no conflicts)