use partial primary key if another index can prevent filesort

The fix for bug #28404 causes the covering ordering indexes to be 
preferred unconditionally over non-covering and ref indexes.

Fixed by comparing the cost of using a covering index to the cost of
using a ref index even for covering ordering indexes.
Added an assertion to clarify the condition the local variables should
be in.

purge_relay_logs() did not propagate an error happend in count_relay_log_space().

Fixed with the suggestesd setting the error= true.
Note, propagation generally out of purge_relay_logs() was fixed for Bug #44179,
and the issue does not exist in 6.0 thanks to a patch for WL#2775.

Based upon patch contributed by Stewart Smith

the auto_increment value
      
This is an alternative patch that instead of allowing RECREATE TABLE
on TRUNCATE TABLE it implements reset_auto_increment that is called
after delete_all_rows.

Note: this bug was fixed by Mattias Jonsson:
Pusing this patch: http://lists.mysql.com/commits/70370

Item_field::fix_fields()

With ibmdb2i_create_index_option set to 1, creating an IBMDB2I table
with a primary key should produce an additional index that uses EBCDIC
hexadecimal sorting. However, this does not work. Adding indexes that
are not primary keys does work. The ibmdb2i_create_index_option should
be honoured when creating a table with a primary key.

This patch adds code to the create() function to check for the value
of the ibmdb2i_create_index_option variable and, when appropriate, to 
generate a *HEX-based shadow index in DB2 for the primary key. Previously 
this behavior was limited to secondary indexes.

Additionally, this patch restricts the creation of shadow indexes to
cases in which a non-*HEX sort sequence is used, as the documentation
for ibmdb2i_create_index_option describes. Previously, the shadow index
would in some cases be created even when the MySQL-specific index used
*HEX sorting, leading to redundant indexes.

Finally, the code used to generate the list of fields for indexes 
and the code used to generate the SQL statement for the shadow
indexes has been refactored into individual functions.

Added code to the .test file to skip this test on Win64 for PB2 stability.
Please remove this code when the bug is fixed.

Had attempted to disable this test on Windows only, but the nature of this bug
does not allow for this.  The master.opt file is processed before anything in 
in the actual test.  As a result, we must use disabled.def files to ensure
these tests are skipped on the problematic platforms.

Removed Windows-only code and updated the proper disabled.def files accordingly.

GHz.

Some collations were causing IBMDB2I to report
inaccurate key range estimations to the optimizer
for LIKE clauses that select substrings. This can
be seen by running EXPLAIN. This problem primarily
affects multi-byte and unicode character sets.

This patch involves substantial changes to several
modules. There are a number of problems with the
character set and collation handling. These problems
have been or are being fixed,  and a comprehensive
test has been included which should provide much
better coverage than there was before. This test
is enabled only for IBM i 6.1, because that version
has support for the greatest number of collations.

timeout
            
In STMT and MIXED modes, a statement that changes both non-transactional and
transactional tables must be written to the binary log whenever there are
changes to non-transactional tables. This means that the statement gets into the
binary log even when the changes to the transactional tables fail. In particular
, in the presence of a failure such statement is annotated with the error number
and wrapped in a begin/rollback. On the slave, while applying the statement, it
is expected the same failure and the rollback prevents the transactional changes
to be persisted.
            
Unfortunately, statements that fail due to concurrency issues (e.g. deadlocks,
timeouts) are logged in the same way causing the slave to stop as the statements
are applied sequentially by the SQL Thread. To fix this bug, we automatically
ignore concurrency failures on the slave. Specifically, the following failures
are ignored: ER_LOCK_WAIT_TIMEOUT, ER_LOCK_DEADLOCK and ER_XA_RBDEADLOCK.