For queries like
update t1 set ... where <unique key> order by ... limit ...
we need to handle the fact that unique keys allow NULL
values, and hence can return more than one row.


sql/opt_range.cc:
  When the unique key has multiple key parts,
  check each key_part for nullability, rather than the first key part.
  (s/key->part ==/key_tree->part ==/)
  
  Also: revert the if() test, for better readability.

	       IT IS DONE IN-PLACE

With change buffer enabled, InnoDB doesn't write a transaction log
record when it merges a record from the insert buffer to an secondary
index page if the insertion is performed as an update-in-place.

Fixed by logging the 'update-in-place' operation on secondary index
pages.

Approved by Marko. rb#2429

                WITH MY_B_VPRINTF()

[Merge from 5.1]

                WITH MY_B_VPRINTF()
Issue         : In LP 64 machine max long value can be 20 digit
                decimal value. But in my_b_vprintf() the intermediate
                buffer storage used is 17 bytes length. This will lead to
                buffer overflow.
Solution      : Increased the buffer storage from 17 to 32 bytes.
                code is backported from 5.6


mysys/mf_iocache2.c:
  In function my_b_vprintf increased the size of local buff from 17 to
  32 bytes.

Postfix, suppress the new warning generated by the bug's fix.

Dump thread may encounter an error when reading events from the active binlog
file. However the errors may be temporary, so dump thread will try to read
the event again. But dump thread seeked to an wrong position, it caused some
events was sent twice.

To fix the bug, prev_pos is defined out the while loop and is set the correct
position after reading every event correctly.

This patch also make binlog_can_be_corrupted more accurate, only the binlogs
not closed normally are marked binlog_can_be_corrupted.

Finally, two warnings are added when dump threads encounter the temporary
errors.

Merging from 5.1 to 5.5

      
Reverting the patch. Because this change is not to me made for GA versions.

Do not call abs(INT_MIN) as the result is undefined.

Add missing initialization in lex_start()

              FILES SPECIFIED WITH THE BASEDIR OPTION

Reverting the patch. Because asked for second review.

               DO WHAT YOU EXPECT"

Fix info:
--------

Backport of the deprecation bug fix (WL#5265) for global variable
'THREAD_CONCURRENCY' from mysql-5.6 to mysql-5.5

Note: With this backport, certain additional deprecation warnings
      would be reported under error conditions while setting the
      global/session variables.

	       CONTAINING NULL

Problem:-
In MySQL, We can obtain the number of distinct expression
combinations that do not contain NULL by giving a list of 
expressions in COUNT(DISTINCT).
However rows with NULL values are
incorrectly included in the count when loose index scan is 
used.

Analysis:-
In case of loose index scan, we check whether the field is null or 
not and increase the count in Item_sum_count::add().
But there we are checking for the first field in COUNT(DISTINCT), 
not for every field. This is causing an incorrect result.

Solution:-
Check all field in Item_sum_count::add(), whether there values 
are null or not. Then only increment the count.
******
Bug#17222452 - SELECT COUNT(DISTINCT A,B) INCORRECTLY COUNTS ROWS 
	       CONTAINING NULL

Problem:-
In MySQL, We can obtain the number of distinct expression
combinations that do not contain NULL by giving a list of 
expressions in COUNT(DISTINCT).
However rows with NULL values are
incorrectly included in the count when loose index scan is 
used.

Analysis:-
In case of loose index scan, we check whether the field is null or 
not and increase the count in Item_sum_count::add().
But there we are checking for the first field in COUNT(DISTINCT), 
not for every field. This is causing an incorrect result.

Solution:-
Check all field in Item_sum_count::add(), whether there values 
are null or not. Then only increment the count.

              SPECIFIED WITH THE BASEDIR OPTION

Description: The mysql_plugin client attempts to remove any
filename specified to the --basedir option. The problem is 
that if the filename does not end with a slash, it will 
attempt to unlink it, which succeeds for files, but not for 
directories.

Analysis: When we are starting mysql_plugin with basedir 
option and if we are giving path of a file as basedir, it 
deletes that file. It was because it uses a function 
my_delete which unlinks the file path given.

Fix:  As a fix we replace that line using another function 
my_free, which will only free the  pointer which is having 
that file path.

No commit message

Memory Leak in mysql_options() was caused by missing call
to my_free() in MYSQL_SET_CLIENT_IP branch. Fixed by adding
my_free() to cleanup mysql->options.client_ip value before
assigning new value.

Memory Leak in mysql_options() was caused by missing call
to my_free() in MYSQL_SET_CLIENT_IP branch. Fixed by adding
my_free() to cleanup mysql->options.client_ip value before
assigning new value.

             ERROR HANDLING CODE 

BACKGROUND:
There can be a potential crash due to buffer overrun in 
SSL error handling code due to missing comma in
ssl_error_string[] array in viosslfactories.c.

ANALYSIS:
Found by code Inspection.

FIX:
Added the missing comma in SSL error handling code
in ssl_error_string[] array in viosslfactories.c.

             ERROR HANDLING CODE 

BACKGROUND:
There can be a potential crash due to buffer overrun in 
SSL error handling code due to missing comma in
ssl_error_string[] array in viosslfactories.c.

ANALYSIS:
Found by code Inspection.

FIX:
Added the missing comma in SSL error handling code
in ssl_error_string[] array in viosslfactories.c.

Problem:-
Second execution of prepared statement for query with 
parameter in limit clause, causes an assert when using 
connectors (e.g., Connector C).  


Analysis:-
In prepared statement, LIMIT parameters can be
specified using '?' markers. Value for the parameter can
be supplied while executing the prepared statement.

Passing string, float or double values for LIMIT clause
works well from command-line client. That's because, while 
setting the LIMIT parameter value from a user-variable,
the value is converted to integer value.

However, when prepared statement is executed from other
interfaces as J connectors, or C applications etc,
the value for the parameters are sent to the server
with execute command. Each item in command has value and
the data TYPE. So, while setting parameter values
from this log, value is set to all the parameters
with the same data type as passed.
Here, we have the logic to convert the value to change the 
state and item_type if it is part of LIMIT parameter and 
its item_type is not INT.
But when we reset this parameter we save the item_type but change 
state. So on second execution we have old item_type but our state 
has been changed, which make us to use string type variable 
in Item_param::query_str_val(). This cause an assert.

Fix:
Instead of checking the item_type of the parameter, check for 
the state of the parameter. As state value are reset everytime
we execute the statement.

ER_LOCK_WAIT_TIMEOUT".

The problem was that after changes caused by fix bug 14188793 "DEADLOCK
CAUSED BY ALTER TABLE DOEN'T CLEAR STATUS OF ROLLBACKED TRANSACTION"/
bug 17054007 "TRANSACTION IS NOT FULLY ROLLED BACK IN CASE OF INNODB
DEADLOCK implicit rollback of transaction which occurred on ER_LOCK_DEADLOCK
(and ER_LOCK_WAIT_TIMEOUT if innodb_rollback_on_timeout option was set)
didn't start new transaction in @@autocommit=1 mode.

Such behavior although consistent with behavior of explicit ROLLBACK has
broken expectations of users and backward compatibility assumptions.

This patch fixes problem by reverting to starting new transaction
in 5.5/5.6.

The plan is to keep new behavior in trunk so the code change from this
patch is to be null-merged there.

               "SHOW PROCESSLIST"

Follow up path, addressing pb2 test failure.

No commit message

Problem:-
In a Procedure, when we are comparing value of select query 
with IN clause and they both have different collation, cause 
error on first time execution and assert second time.
procedure will have query like
set @x = ((select a from t1) in (select d from t2));<---proc1
              sel1                   sel2

Analysis:-
When we execute this proc1(first time)
While resolving the fields of user variable, we will call 
Item_in_subselect::fix_fields while will resolve sel2. There 
in Item_in_subselect::select_transformer, we evaluate the 
left expression(sel1) and store it in Item_cache_* object 
(to avoid re-evaluating it many times during subquery execution) 
by making Item_in_optimizer class.
While evaluating left expression we will prepare sel1.
After that, we will put a new condition in sel2  
in Item_in_subselect::select_transformer() which will compare 
t2.d and sel1(which is cached in Item_in_optimizer).

Later while checking the collation in agg_item_collations() 
we get error and we cleanup the item. While cleaning up we cleaned 
the cached value in Item_in_optimizer object.

When we execute the procedure second time, we have condition for 
sel2 and while setup_cond(), we can't able to find reference item 
as it is cleanup while item cleanup.So it assert.


Solution:-
We should not cleanup the cached value for Item_in_optimizer object, 
if we have put the condition to subselect.

Problem:-
In a Procedure, when we are comparing value of select query 
with IN clause and they both have different collation, cause 
error on first time execution and assert second time.
procedure will have query like
set @x = ((select a from t1) in (select d from t2));<---proc1
              sel1                   sel2

Analysis:-
When we execute this proc1(first time)
While resolving the fields of user variable, we will call 
Item_in_subselect::fix_fields while will resolve sel2. There 
in Item_in_subselect::select_transformer, we evaluate the 
left expression(sel1) and store it in Item_cache_* object 
(to avoid re-evaluating it many times during subquery execution) 
by making Item_in_optimizer class.
While evaluating left expression we will prepare sel1.
After that, we will put a new condition in sel2  
in Item_in_subselect::select_transformer() which will compare 
t2.d and sel1(which is cached in Item_in_optimizer).

Later while checking the collation in agg_item_collations() 
we get error and we cleanup the item. While cleaning up we cleaned 
the cached value in Item_in_optimizer object.

When we execute the procedure second time, we have condition for 
sel2 and while setup_cond(), we can't able to find reference item 
as it is cleanup while item cleanup.So it assert.


Solution:-
We should not cleanup the cached value for Item_in_optimizer object, 
if we have put the condition to subselect.

No commit message

No commit message

         in 5.5, 5.6, 5.7.