MDEV-6789 segfault in Item_func_from_unixtime::get_date on updating table with virtual columns
* prohibit VALUES in partitioning expression
* prohibit user and system variables in virtual column expressions
* fix Item_func_date_format to cache locale (for %M/%W to return the same as MONTHNAME/DAYNAME)
* fix Item_func_from_unixtime to cache time_zone directly, not THD (and not to crash)
* added tests for other incorrectly allowed (in vcols) functions to see that they don't crash
When parsing a field declaration, grab type information from LEX before it's overwritten
by further rules. Pass type information through the parser stack to the rule that needs it.
The test runs a query in one thread, then in another queries the processlist
and expects to find the first thread in the COM_SLEEP state. The problem is
that the thread signals completion to the client before changing to COM_SLEEP
state, so there is a window where the other thread can see the wrong state.
A previous attempt to fix this was ineffective. It set a DEBUG_SYNC to handle
proper waiting, but unfortunately that DEBUG_SYNC point ended up triggering
already at the end of SET DEBUG_SYNC=xxx, so the wait was ineffective.
Fix it properly now (hopefully) by ensuring that we wait for the DEBUG_SYNC
point to trigger at the end of the SELECT SLEEP(), not just at the end of
SET DEBUG_SYNC=xxx.
(Backport to 5.3)
(Attempt #2)
- Don't attempt to use BKA for materialized derived tables. The
table is neither filled nor fully opened yet, so attempt to
call handler->multi_range_read_info() causes crash.
(Backport to 5.3)
(variant #2, with fixed coding style)
- Make Mrr_ordered_index_reader::resume_read() restore index position
only if it was saved before with Mrr_ordered_index_reader::interrupt_read().
- TABLE::create_key_part_by_field() should not set PART_KEY_FLAG in field->flags
= The reason is that it is used by hash join code which calls it to create a hash
table lookup structure. It doesn't create a real index.
= Another caller of the function is TABLE::add_tmp_key(). Made it to set the flag itself.
- The differences in join_cache.result could also be observed before this patch: one
could put "FLUSH TABLES" before the queries and get exactly the same difference.
Description:- Replace, the string replacement utility fails
on the windows platform.
Analysis:- The utility takes files and multiple string
pairs as input. In the windows platform, the utility maps
the standard input incorrectly (Considers 0 as the fd for
standard input instead of 2048 on windows). Hence when the
input file is supplied to the utility due to the incorrect
mapping, a bad file descriptor error is generated causing
the utility to exit with an error.
Fix:- "my_fileno()" is used for getting the correct file
despscriptor for standard input.
Description:- Replace, the string replacement utility fails
on the windows platform.
Analysis:- The utility takes files and multiple string
pairs as input. In the windows platform, the utility maps
the standard input incorrectly (Considers 0 as the fd for
standard input instead of 2048 on windows). Hence when the
input file is supplied to the utility due to the incorrect
mapping, a bad file descriptor error is generated causing
the utility to exit with an error.
Fix:- "my_fileno()" is used for getting the correct file
despscriptor for standard input.
I think I finally found the problem, managed to reproduce locally using a
sleep in the test case to simulate the particular race condition that causes
the test to fail often in Buildbot.
The test starts an ALTER TABLE that does repair by sort in one thread, then
another thread waits for the sort to be visible in SHOW PROCESSLIST and runs a
SHOW statement in parallel.
The problem happens when the sort manages to run to completion before the
other thread has the time to look at SHOW PROCESSLIST. In this case, the wait
times out because the state looked for has already passed.
Earlier I added some DEBUG_SYNC to prevent this race, but it turns out that
DEBUG_SYNC itself changes the state in the processlist. So when the debug sync
point was hit, the processlist was showing the wrong state, so the wait would
still time out.
Fixed now by looking for the processlist to contain either the "Repair by
sorting" state or the debug sync wait stage.
Also clean up previous attempts to fix it. Set the wait timeout back to
reasonable 60 seconds, and simplify the DEBUG_SYNC operations to work closer
to how the original test case was intended.
1. Do not use NULL `info' field in processlist to select the thread of
interest. This can fail if the read of processlist ends up happening after
REAP succeeds, but before the `info' field is reset. Instead, select on the
CONNECTION_ID(), making sure we still scan the whole list to trigger the same
code as in the original test case.
2. Wait for the query to really complete before reading it in the
processlist. When REAP returns, it only means that ack has been sent to
client, the reset of query stage happens a bit later in the code.
Add missing REAP to the test.
A later test failed with strange incorrect values for COM_SELECT
in information_schema.global_status. Since global_status is updated
at the end of session activity, it seems appropriate to ensure that
all background connections have completed before accessing it.
(I checked that the original bug still triggers the test case after
the modification with REAP).
- test_if_skip_sort_order()/create_ref_for_key() may change table
access from EQ_REF(index1) to REF(index2).
- Doing so doesn't make much sense from optimization POV, but since
they are doing it, they should update tab->read_record.unlock_row
accordingly.
Don't double-check privileges for a column in the GROUP BY that refers to
the same column in SELECT clause. Privileges were already checked for SELECT clause.
AND IS_USED_LOCK().
Analysis:
-----------
In functions Item_func_is_free_lock::val_int() and
Item_func_is_used_lock::val_int(), for the specified user lock
name, pointer to its "User_level_lock" object is obtained from hash
"hash_user_locks". Mutex "LOCK_user_locks" is acquired for this
and released immediately. And we are accessing members of
User_level_lock after releasing the mutex. If same user lock is
deleted(released) from concurrent thread then accessing members
results in invalid(freed) memory access issue.
Deleting of user lock is also protected from the mutex
"LOCK_user_locks". Since this mutex is released in "val_int"
functions mentioned above, delete operation proceeds while concurrent
thread tries to access its members.
With the test case, valgrind reports invalid read issues in val_int
functions.
Fix:
-----------
To fix this issue, in "val_int" function of classes
"Item_func_is_free_lock" and "Item_func_is_used_lock", now releasing
mutex "LOCK_user_locks" after accessing User_level_lock members.
AND IS_USED_LOCK().
Analysis:
-----------
In functions Item_func_is_free_lock::val_int() and
Item_func_is_used_lock::val_int(), for the specified user lock
name, pointer to its "User_level_lock" object is obtained from hash
"hash_user_locks". Mutex "LOCK_user_locks" is acquired for this
and released immediately. And we are accessing members of
User_level_lock after releasing the mutex. If same user lock is
deleted(released) from concurrent thread then accessing members
results in invalid(freed) memory access issue.
Deleting of user lock is also protected from the mutex
"LOCK_user_locks". Since this mutex is released in "val_int"
functions mentioned above, delete operation proceeds while concurrent
thread tries to access its members.
With the test case, valgrind reports invalid read issues in val_int
functions.
Fix:
-----------
To fix this issue, in "val_int" function of classes
"Item_func_is_free_lock" and "Item_func_is_used_lock", now releasing
mutex "LOCK_user_locks" after accessing User_level_lock members.
Avoided exponential recursive calls of JOIN_CACHE::join_records() in the case
of non-nested outer joins.
A different solution is required to resolve this performance problem for
nested outer joins.
Don't restore the whole of thd->server_status after a routine invocation,
only restore SERVER_STATUS_CURSOR_EXISTS and SERVER_STATUS_LAST_ROW_SENT,
as --ps --embedded needs.
In particular, don't restore SERVER_STATUS_IN_TRANS.
COLLATIONS ARE USED.
ISSUE :
-------
Code points of HALF WIDTH KATAKANA in SJIS/CP932 range from
A1 to DF. In function my_wildcmp_mb_bin_impl while comparing
such single byte code points, there is a code which compares
signed character with unsigned character. Because of this,
comparisons of two same code points representing a HALF
WIDTH KATAKANA character always fails.
Solution:
---------
A code point of HALF WIDTH KATAKANA at-least need 8 bits.
Promoting the variable from uchar to int will fix the issue.
mysql-test/t/ctype_cp932.test:
Tests which have conditions
LIKE 'STRING PATTERN WITH HALF WIDTH KATAKANA'.
strings/ctype-mb.c:
A code point of HALF WIDTH KATAKANA at-least need 8 bits.
Promoting the variable from uchar to int will fix the issue.
COLLATIONS ARE USED.
ISSUE :
-------
Code points of HALF WIDTH KATAKANA in SJIS/CP932 range from
A1 to DF. In function my_wildcmp_mb_bin_impl while comparing
such single byte code points, there is a code which compares
signed character with unsigned character. Because of this,
comparisons of two same code points representing a HALF
WIDTH KATAKANA character always fails.
Solution:
---------
A code point of HALF WIDTH KATAKANA at-least need 8 bits.
Promoting the variable from uchar to int will fix the issue.
~40% bugfixed(*) applied
~40$ bugfixed reverted (incorrect or we're not buggy)
~20% bugfixed applied, despite us being not buggy
(*) only changes in the server code, e.g. not cmakefiles
We don't support changing tc_log implementation at run time.
If the first XA-capable engine is loaded with INSTALL PLUGIN - disable its
XA capabilities with a warning
MySQL Bug#71095: Wrong results with PARTITION BY LIST COLUMNS()
MySQL Bug#72803: Wrong "Impossible where" with LIST partitioning
MDEV-6240: Wrong "Impossible where" with LIST partitioning
- Backprot the fix from MySQL Bug#71095.
- When traversing JOIN_TABs with first_linear_tab/next_linear_tab(), don't forget
to enter the semi-join nest when it is the first table in the join order.
Failure to do so could cause e.g. I_S tables not to be filled.
GOES AWAY, MYSQL QUITS WORKING.
Analysis:
-----------------
Issue in this bug and in bug 11907705 is, the socket file or
fifo file is set for general log at command line while starting
the server. But currently, only regular file can be set for the
general log. Instead of reporting any error, the provided files
are opened for writing and continued. Because of this issues
mentioned in the bug reports are seen.
As mentioned, only when any non-regular file is set for general
log at command line while starting the server, these issues are
seen. If general log file is set to non-regular file from CLI
using system variable general_log_file then error is reported.
These issues can also be faced with slow query log file, if it is
set to non-regular file.
Fix:
-----------------
Currently while starting the server if we fail to open log file
then we report an error, disable logging to file and continue.
To fix issue reported code is modified to check whether file
is regular file or not before opening it. If file is not a
regular file then error is logged to error log and logging to
file is disabled.
GOES AWAY, MYSQL QUITS WORKING.
Analysis:
-----------------
Issue in this bug and in bug 11907705 is, the socket file or
fifo file is set for general log at command line while starting
the server. But currently, only regular file can be set for the
general log. Instead of reporting any error, the provided files
are opened for writing and continued. Because of this issues
mentioned in the bug reports are seen.
As mentioned, only when any non-regular file is set for general
log at command line while starting the server, these issues are
seen. If general log file is set to non-regular file from CLI
using system variable general_log_file then error is reported.
These issues can also be faced with slow query log file, if it is
set to non-regular file.
Fix:
-----------------
Currently while starting the server if we fail to open log file
then we report an error, disable logging to file and continue.
To fix issue reported code is modified to check whether file
is regular file or not before opening it. If file is not a
regular file then error is logged to error log and logging to
file is disabled.
Bug#16415173 CRLF INSTEAD OF LF IN SQL-BENCH SCRIPTS
Correct perms and converts from Windows style to UNIX style line endings on some files.
Fix perms on installed ini files.
(MySQL 5.5 version)
Bug#16415173 CRLF INSTEAD OF LF IN SQL-BENCH SCRIPTS
Correct perms and converts from Windows style to UNIX style line endings on some files.
Fix perms on installed ini files.
(MySQL 5.5 version)
CORRUPTS FRM
Analysis:
---------
ALTER TABLE on a partitioned table resulted in the wrong
engine being written into the table's FRM file and displayed
in SHOW CREATE TABLE.
The prep_alter_part_table() modifies the partition_info object
for TABLE instance representing the old version of table.
If the ALTER TABLE ENGINE statement fails, the partition_info
object for the TABLE contains the altered storage engine name.
The SHOW CREATE TABLE uses the TABLE object to display the table
information, hence displays incorrect storage engine for the table.
Also a subsequent successful ALTER TABLE operation will write the
incorrect engine information into the FRM file.
Fix:
---
A copy of the partition_info object is created before modification so
that any changes would not cause the the original partition_info object
to be modified if the ALTER TABLE fails.(Backported part of the code
provided as fix for bug#14156617 in mysql-5.6.6).
CORRUPTS FRM
Analysis:
---------
ALTER TABLE on a partitioned table resulted in the wrong
engine being written into the table's FRM file and displayed
in SHOW CREATE TABLE.
The prep_alter_part_table() modifies the partition_info object
for TABLE instance representing the old version of table.
If the ALTER TABLE ENGINE statement fails, the partition_info
object for the TABLE contains the altered storage engine name.
The SHOW CREATE TABLE uses the TABLE object to display the table
information, hence displays incorrect storage engine for the table.
Also a subsequent successful ALTER TABLE operation will write the
incorrect engine information into the FRM file.
Fix:
---
A copy of the partition_info object is created before modification so
that any changes would not cause the the original partition_info object
to be modified if the ALTER TABLE fails.(Backported part of the code
provided as fix for bug#14156617 in mysql-5.6.6).
- Filesort has an optmization where it reads only columns that are
needed before the sorting is done.
- When ref(_or_null) is picked by the join optimizer, it may remove parts
of WHERE clause that are guaranteed to be true.
- However, if we use quick select, we must put all of the range columns into the
read set. Not doing so will may cause us to fail to detect the end of the range.
- When range optimizer cannot the lookup value into [VAR]CHAR(n) column,
it should produce:
= "Impossible range" for equality
= "no range" for non-equalities.
MDEV-6099 Bad results for DATE_ADD(.., INTERVAL 2000000000000000000.0 SECOND)
MDEV-6097 Inconsistent results for CAST(int,decimal,double AS DATETIME)
MDEV-6100 No warning on CAST(9000000 AS TIME)
We have to run the derived table prepare before the unique table check to mark the derived table (in this case the unique table check can turn that table to materialized one).
Bug #18167356: EXPLAIN W/ EXISTS(SELECT* UNION SELECT*)
WHERE ONE OF SELECT* IS DISTINCT FAILS.
the bugfix itself was not merged - MariaDB doesn't have this bug.
- When the optimizer chose LooseScan, make_join_readinfo() should
use the index that was chosen for LooseScan, and should not try
to find a better (shortest) index.
"HAVING SUM(DISTINCT)": WRONG RESULTS.
ISSUE:
------
If a query uses loose index scan and it has both
AGG(DISTINCT) and MIN()/MAX()functions. Then, result values
of MIN/MAX() is set improperly.
When query has AGG(DISTINCT) then end_select is set to
end_send_group. "end_send_group" keeps doing aggregation
until it sees a record from next group. And, then it will
send out the result row of that group.
Since query also has MIN()/MAX() and loose index scan is
used, values of MIN/MAX() are set as part of loose index
scan itself. Setting MIN()/MAX() values as part of loose
index scan overwrites values computed in end_send_group.
This caused invalid result.
For such queries to work loose index scan should stop
performing MIN/MAX() aggregation. And, let end_send_group to
do the same. But according to current design loose index
scan can produce only one row per group key. If we have both
MIN() and MAX() then it has to give two records out. This is
not possible as interface has to use common buffer
record[0]! for both records at a time.
SOLUTIONS:
----------
For such queries to work we need a new interface for loose
index scan. Hence, do not choose loose_index_scan for such
cases. So a new rule SA7 is introduced to take care of the
same.
SA7: "If Q has both AGG_FUNC(DISTINCT ...) and
MIN/MAX() functions then loose index scan access
method is not used."
mysql-test/r/group_min_max.result:
Expected result.
mysql-test/t/group_min_max.test:
1. Test with various combination of AGG(DISTINCT) and
MIN(), MAX() functions.
2. Corrected the plan for old queries.
sql/opt_range.cc:
A new rule SA7 is introduced.
"HAVING SUM(DISTINCT)": WRONG RESULTS.
ISSUE:
------
If a query uses loose index scan and it has both
AGG(DISTINCT) and MIN()/MAX()functions. Then, result values
of MIN/MAX() is set improperly.
When query has AGG(DISTINCT) then end_select is set to
end_send_group. "end_send_group" keeps doing aggregation
until it sees a record from next group. And, then it will
send out the result row of that group.
Since query also has MIN()/MAX() and loose index scan is
used, values of MIN/MAX() are set as part of loose index
scan itself. Setting MIN()/MAX() values as part of loose
index scan overwrites values computed in end_send_group.
This caused invalid result.
For such queries to work loose index scan should stop
performing MIN/MAX() aggregation. And, let end_send_group to
do the same. But according to current design loose index
scan can produce only one row per group key. If we have both
MIN() and MAX() then it has to give two records out. This is
not possible as interface has to use common buffer
record[0]! for both records at a time.
SOLUTIONS:
----------
For such queries to work we need a new interface for loose
index scan. Hence, do not choose loose_index_scan for such
cases. So a new rule SA7 is introduced to take care of the
same.
SA7: "If Q has both AGG_FUNC(DISTINCT ...) and
MIN/MAX() functions then loose index scan access
method is not used."
SHOW PROCESSLIST, SHOW BINLOGS
Fixing post push test failure (MTR does not like giving
127.0.0.1 for localhost incase of --embedded run, it thinks
it is an external ip address)
SHOW PROCESSLIST, SHOW BINLOGS
Fixing post push test failure (MTR does not like giving
127.0.0.1 for localhost incase of --embedded run, it thinks
it is an external ip address)
SHOW PROCESSLIST, SHOW BINLOGS
Problem: A deadlock was occurring when 4 threads were
involved in acquiring locks in the following way
Thread 1: Dump thread ( Slave is reconnecting, so on
Master, a new dump thread is trying kill
zombie dump threads. It acquired thread's
LOCK_thd_data and it is about to acquire
mysys_var->current_mutex ( which LOCK_log)
Thread 2: Application thread is executing show binlogs and
acquired LOCK_log and it is about to acquire
LOCK_index.
Thread 3: Application thread is executing Purge binary logs
and acquired LOCK_index and it is about to
acquire LOCK_thread_count.
Thread 4: Application thread is executing show processlist
and acquired LOCK_thread_count and it is
about to acquire zombie dump thread's
LOCK_thd_data.
Deadlock Cycle:
Thread 1 -> Thread 2 -> Thread 3-> Thread 4 ->Thread 1
The same above deadlock was observed even when thread 4 is
executing 'SELECT * FROM information_schema.processlist' command and
acquired LOCK_thread_count and it is about to acquire zombie
dump thread's LOCK_thd_data.
Analysis:
There are four locks involved in the deadlock. LOCK_log,
LOCK_thread_count, LOCK_index and LOCK_thd_data.
LOCK_log, LOCK_thread_count, LOCK_index are global mutexes
where as LOCK_thd_data is local to a thread.
We can divide these four locks in two groups.
Group 1 consists of LOCK_log and LOCK_index and the order
should be LOCK_log followed by LOCK_index.
Group 2 consists of other two mutexes
LOCK_thread_count, LOCK_thd_data and the order should
be LOCK_thread_count followed by LOCK_thd_data.
Unfortunately, there is no specific predefined lock order defined
to follow in the MySQL system when it comes to locks across these
two groups. In the above problematic example,
there is no problem in the way we are acquiring the locks
if you see each thread individually.
But If you combine all 4 threads, they end up in a deadlock.
Fix:
Since everything seems to be fine in the way threads are taking locks,
In this patch We are changing the duration of the locks in Thread 4
to break the deadlock. i.e., before the patch, Thread 4
('show processlist' command) mysqld_list_processes()
function acquires LOCK_thread_count for the complete duration
of the function and it also acquires/releases
each thread's LOCK_thd_data.
LOCK_thread_count is used to protect addition and
deletion of threads in global threads list. While show
process list is looping through all the existing threads,
it will be a problem if a thread is exited but there is no problem
if a new thread is added to the system. Hence a new mutex is
introduced "LOCK_thd_remove" which will protect deletion
of a thread from global threads list. All threads which are
getting exited should acquire LOCK_thd_remove
followed by LOCK_thread_count. (It should take LOCK_thread_count
also because other places of the code still thinks that exit thread
is protected with LOCK_thread_count. In this fix, we are changing
only 'show process list' query logic )
(Eg: unlink_thd logic will be protected with
LOCK_thd_remove).
Logic of mysqld_list_processes(or file_schema_processlist)
will now be protected with 'LOCK_thd_remove' instead of
'LOCK_thread_count'.
Now the new locking order after this patch is:
LOCK_thd_remove -> LOCK_thd_data -> LOCK_log ->
LOCK_index -> LOCK_thread_count
SHOW PROCESSLIST, SHOW BINLOGS
Problem: A deadlock was occurring when 4 threads were
involved in acquiring locks in the following way
Thread 1: Dump thread ( Slave is reconnecting, so on
Master, a new dump thread is trying kill
zombie dump threads. It acquired thread's
LOCK_thd_data and it is about to acquire
mysys_var->current_mutex ( which LOCK_log)
Thread 2: Application thread is executing show binlogs and
acquired LOCK_log and it is about to acquire
LOCK_index.
Thread 3: Application thread is executing Purge binary logs
and acquired LOCK_index and it is about to
acquire LOCK_thread_count.
Thread 4: Application thread is executing show processlist
and acquired LOCK_thread_count and it is
about to acquire zombie dump thread's
LOCK_thd_data.
Deadlock Cycle:
Thread 1 -> Thread 2 -> Thread 3-> Thread 4 ->Thread 1
The same above deadlock was observed even when thread 4 is
executing 'SELECT * FROM information_schema.processlist' command and
acquired LOCK_thread_count and it is about to acquire zombie
dump thread's LOCK_thd_data.
Analysis:
There are four locks involved in the deadlock. LOCK_log,
LOCK_thread_count, LOCK_index and LOCK_thd_data.
LOCK_log, LOCK_thread_count, LOCK_index are global mutexes
where as LOCK_thd_data is local to a thread.
We can divide these four locks in two groups.
Group 1 consists of LOCK_log and LOCK_index and the order
should be LOCK_log followed by LOCK_index.
Group 2 consists of other two mutexes
LOCK_thread_count, LOCK_thd_data and the order should
be LOCK_thread_count followed by LOCK_thd_data.
Unfortunately, there is no specific predefined lock order defined
to follow in the MySQL system when it comes to locks across these
two groups. In the above problematic example,
there is no problem in the way we are acquiring the locks
if you see each thread individually.
But If you combine all 4 threads, they end up in a deadlock.
Fix:
Since everything seems to be fine in the way threads are taking locks,
In this patch We are changing the duration of the locks in Thread 4
to break the deadlock. i.e., before the patch, Thread 4
('show processlist' command) mysqld_list_processes()
function acquires LOCK_thread_count for the complete duration
of the function and it also acquires/releases
each thread's LOCK_thd_data.
LOCK_thread_count is used to protect addition and
deletion of threads in global threads list. While show
process list is looping through all the existing threads,
it will be a problem if a thread is exited but there is no problem
if a new thread is added to the system. Hence a new mutex is
introduced "LOCK_thd_remove" which will protect deletion
of a thread from global threads list. All threads which are
getting exited should acquire LOCK_thd_remove
followed by LOCK_thread_count. (It should take LOCK_thread_count
also because other places of the code still thinks that exit thread
is protected with LOCK_thread_count. In this fix, we are changing
only 'show process list' query logic )
(Eg: unlink_thd logic will be protected with
LOCK_thd_remove).
Logic of mysqld_list_processes(or file_schema_processlist)
will now be protected with 'LOCK_thd_remove' instead of
'LOCK_thread_count'.
Now the new locking order after this patch is:
LOCK_thd_remove -> LOCK_thd_data -> LOCK_log ->
LOCK_index -> LOCK_thread_count
ISSUE:
------
For UNION of selects, rows examined by the query will be sum
of rows examined by individual select operations and rows
examined for union operation. The value of session level
global counter that is used to count the rows examined by a
select statement should be accumulated and reset before it
is used for next select statement. But we have missed to
reset the same. Because of this examined row count of a
select query is accounted more than once.
SOLUTION:
---------
In union reset the session level global counter used to
accumulate count of examined rows after its value is saved.
mysql-test/r/union.result:
Expected output of testcase added.
mysql-test/t/union.test:
Test to verify examined row count of Union operations.
sql/sql_union.cc:
Reset the value of thd->examined_row_count after
accumulating the value.
ISSUE:
------
For UNION of selects, rows examined by the query will be sum
of rows examined by individual select operations and rows
examined for union operation. The value of session level
global counter that is used to count the rows examined by a
select statement should be accumulated and reset before it
is used for next select statement. But we have missed to
reset the same. Because of this examined row count of a
select query is accounted more than once.
SOLUTION:
---------
In union reset the session level global counter used to
accumulate count of examined rows after its value is saved.
Problem:
If there is a predicate on a column referenced by MIN/MAX and
that predicate is not present in all the disjunctions on
keyparts earlier in the compound index, Loose Index Scan will
not return correct result.
Analysis:
When loose index scan is chosen, range optimizer currently
groups all the predicates that contain group parts separately
and minmax parts separately. It therefore applies all the
conditions on the group parts first to the fetched row.
Then in the call to next_max, it processes the conditions
which have min/max keypart.
For ex in the following query:
Select f1, max(f2) from t1 where (f1 = 10 and f2 = 13) or
(f1 = 3) group by f1;
Condition (f2 = 13) would be applied even for rows that
satisfy (f1 = 3) thereby giving wrong results.
Solution:
Do not choose loose_index_scan for such cases. So a new rule
WA2 is introduced to take care of the same.
WA2: "If there are predicates on C, these predicates must
be in conjuction to all predicates on all earlier keyparts
in I."
Todo the same, fix reuses the function get_constant_key_infix().
Since this funciton will fail for all multi-range conditions, it
is re-written to recognize that if the sub-conditions are
equivalent across the disjuncts: it will now succeed.
And to achieve this a new helper function is introduced called
all_same().
The fix also moves the test of NGA3 up to the former only
caller, get_constant_key_infix().
mysql-test/r/group_min_max_innodb.result:
Added test result change for Bug#17909656
mysql-test/t/group_min_max_innodb.test:
Added test cases for Bug#17909656
sql/opt_range.cc:
Introduced Rule WA2 because of Bug#17909656
Problem:
If there is a predicate on a column referenced by MIN/MAX and
that predicate is not present in all the disjunctions on
keyparts earlier in the compound index, Loose Index Scan will
not return correct result.
Analysis:
When loose index scan is chosen, range optimizer currently
groups all the predicates that contain group parts separately
and minmax parts separately. It therefore applies all the
conditions on the group parts first to the fetched row.
Then in the call to next_max, it processes the conditions
which have min/max keypart.
For ex in the following query:
Select f1, max(f2) from t1 where (f1 = 10 and f2 = 13) or
(f1 = 3) group by f1;
Condition (f2 = 13) would be applied even for rows that
satisfy (f1 = 3) thereby giving wrong results.
Solution:
Do not choose loose_index_scan for such cases. So a new rule
WA2 is introduced to take care of the same.
WA2: "If there are predicates on C, these predicates must
be in conjuction to all predicates on all earlier keyparts
in I."
Todo the same, fix reuses the function get_constant_key_infix().
Since this funciton will fail for all multi-range conditions, it
is re-written to recognize that if the sub-conditions are
equivalent across the disjuncts: it will now succeed.
And to achieve this a new helper function is introduced called
all_same().
The fix also moves the test of NGA3 up to the former only
caller, get_constant_key_infix().
Typo leading to not including the last list values (partition).
Also improved pruning to skip last partition if not used.
rb#4762 approved by Aditya and Marko.
Typo leading to not including the last list values (partition).
Also improved pruning to skip last partition if not used.
rb#4762 approved by Aditya and Marko.
- Fixed bug that we where using wrong checksum algorithm when using VARCHAR with fixed lenth rows
- Ensure in myisampack that HA_OPTION_NULL_FIELDS is set for tables with null fields.
mysql-test/r/myisampack.result:
Updated results
mysql-test/t/myisampack.test:
Added more tests
storage/myisam/mi_open.c:
Use correct checksum algorithm when we have VARCHAR fields with fixed length records
storage/myisam/myisampack.c:
Ensure HA_OPTION_NULL_FIELDS is set for tables with null fields.
(This was not set by default for not compressed tables without checksums to keep MyISAM tables compatible with MySQL)
It is triple bug with one test suite:
1. Incorrect outer table detection
2. Incorrect leaf table processing for multi-update (should be full like for usual updates and inserts)
3. ON condition fix_fields() fould be called for all tables of the query.
ARE PERMANENTLY SKIPPED IN 5.5/5.6).
The problem was that some result files were not updated,
so the tests were skipped.
The fix is to record updated result files.
ARE PERMANENTLY SKIPPED IN 5.5/5.6).
The problem was that some result files were not updated,
so the tests were skipped.
The fix is to record updated result files.
Bug#18396916 MAIN.OUTFILE_LOADDATA TEST FAILS ON ARM, AARCH64, PPC/PPC64
The recorded results for the failing tests were wrong.
They were introduced by the patch for
Bug#30946 mysqldump silently ignores --default-character-set when used with --tab
Correct results were returned for platforms where 'char' is implemented as unsigned.
This was reported as
Bug#46895 Test "outfile_loaddata" fails (reproducible)
Bug#11755168 46895: TEST "OUTFILE_LOADDATA" FAILS (REPRODUCIBLE)
The patch for that bug fixed only parts of the problem,
leaving the incorrect results in the .result file.
Solution: use 'uchar' for field_terminator and line_terminator on all platforms.
Also: remove some un-necessary casts, leaving the ones we actually need.
Bug#18396916 MAIN.OUTFILE_LOADDATA TEST FAILS ON ARM, AARCH64, PPC/PPC64
The recorded results for the failing tests were wrong.
They were introduced by the patch for
Bug#30946 mysqldump silently ignores --default-character-set when used with --tab
Correct results were returned for platforms where 'char' is implemented as unsigned.
This was reported as
Bug#46895 Test "outfile_loaddata" fails (reproducible)
Bug#11755168 46895: TEST "OUTFILE_LOADDATA" FAILS (REPRODUCIBLE)
The patch for that bug fixed only parts of the problem,
leaving the incorrect results in the .result file.
Solution: use 'uchar' for field_terminator and line_terminator on all platforms.
Also: remove some un-necessary casts, leaving the ones we actually need.
Both bugs are caused by the same problem: the function optimize_cond() should
update the value of *cond_equal rather than the value of join->cond_equal,
because it is called not only for the WHERE condition, but for the HAVING
condition as well.
LOCAL AND IMPORT ERRORS
Description:
-----------
This bug happens due to the fact that current algorithm is designed
that in the case of LOCAL load of data, in case of the error, the
remaining part of the file is read in order to return the proper
error message to the client side.
But, the problem with current implementation is that data stream
for the client side is cleared only in the case where line delimiters
exist, which is not a case with, for example fixed width
fields.
Fix:
----
Ported patch provided by Sinisa Milivojevic n bug report for this
issue to 5.5+ versions.
As part of this patch code is changed to clear the data stream
by calling new member function "READ_INFO::skip_data_till_eof".
LOCAL AND IMPORT ERRORS
Description:
-----------
This bug happens due to the fact that current algorithm is designed
that in the case of LOCAL load of data, in case of the error, the
remaining part of the file is read in order to return the proper
error message to the client side.
But, the problem with current implementation is that data stream
for the client side is cleared only in the case where line delimiters
exist, which is not a case with, for example fixed width
fields.
Fix:
----
Ported patch provided by Sinisa Milivojevic n bug report for this
issue to 5.5+ versions.
As part of this patch code is changed to clear the data stream
by calling new member function "READ_INFO::skip_data_till_eof".
- With big_tables=ON, materialized table will use Aria (or MyISAM) SE, which
allows prefix key reads. However, the temp.table has rec_per_key=NULL which
causes the optimizer to crash when attempting to read index statistics for a
prefix index read.
- Fixed by providing a rec_per_key array with zeros (i.e. "no statistics data")
The calls of the function remove_eq_conds() may change the and/or structure
of the where conditions. So JOIN::equal_cond should be updated for non-recursive
calls of remove_eq_conds().
The problem was that on opening all tables TL_WRITE, than local tables which is not updated set to TL_READ, but underlying tables of MyISAMmrg left untouched.
Prartition engine has not this problem.
All cases where lock_type assigned is not changed because call of virtual function is not cheap.
Fixed crashing bug for union queries where there was no real tables.
mysql-test/r/group_by.result:
Added test case
mysql-test/t/group_by.test:
Added test case
sql/db.opt:
Removed genrated file
sql/item.cc:
Handled case when table_list->pos_in_tables is not set. Can only happens when there is no real tables in query
As Davi added code like
sav_protocol= thd->protocol
thd->protocol= &thd->protocol_binary
...
thd->protocol= sav_protocol
the fucntions like emb_store_querycache_result() cannot determine
the used protocol testing thd->protocol == &thd->protocol_binary.
Fixed by additional check thd->command == COM_STMT_EXECUTE.
update_used_tables for the the where condition to update cached
indicators of constant subexpressions. It should be done before further
possible simplification of the where condition.
This change caused simplification of the executed where conditions
in many test cases.
MDEV-4556 Server crashes in SEL_ARG::rb_insert with index_merge+index_merge_sort_union, FORCE INDEX
- merge_same_index_scans() may put the same SEL_ARG tree in multiple result plans.
make it call incr_refs() on the SEL_ARG trees that it does key_or() on, because
key_or(sel_arg_tree_1, sel_arg_tree_2) call may invalidate SEL_ARG trees pointed
by sel_arg_tree_1 and sel_arg_tree_2.
The result is EMPTY for a buffer(line, -1), but we still
need one FALSE operation to be stored in the condition.
And we actually add it but forgot to alloc memory to store it.
- The problem was that JOIN::prepare() tried to set TABLE::maybe_null
for a table in join. Non-merged semi-join tables 1) are present as
join's base tables on second EXECUTE, but 2) do not yet have a TABLE
object.
Worked around the problem by putting mixed_implicit_grouping into JOIN
object, and then passing it to JTBM tables in setup_jtbm_semi_joins().
(This is attempt at fix#2) (re-commit with fixed typo)
- Moved the testcase from partition_test to partition_innodb.test where it can really work.
- Made ordered index scans over ha_partition tables to satisfy ROR property for
the case where underlying table uses extended keys.
The problem was that a big record was allocated on the stack, which casued stack to run out.
Fixed by using my_safe_alloca() instead of my_alloca() when allocating records.
Now only records <= 16384 are allocated on the stack.
mysql-test/r/stack-crash.result:
Added test case
mysql-test/t/stack-crash.test:
Added test case
storage/maria/ma_blockrec.c:
Use my_safe_alloca() instead of my_alloca()
storage/maria/ma_dynrec.c:
Use my_safe_alloca() instead of my_alloca()
storage/maria/maria_def.h:
Added MARIA_MAX_RECORD_ON_STACK
storage/maria/maria_pack.c:
Use my_safe_alloca() instead of my_alloca()
MDEV-5555: Incorrect index_merge on BTREE indices
- In ha_partition, make ordered index reads return rows in rowid order
when index columns are the same.
Deadlock happened due to mixed lock order.
CREATE/DROP function: wrlock(THR_LOCK_udf) -> lock(LOCK_open)
SELECT from view: lock(LOCK_open) -> rdlock(THR_LOCK_udf)
Fixed CREATE/DROP function so that LOCK_open does not intersect with
wrlock(THR_LOCK_udf).
10.0 is not affected: it doesn't hold LOCK_open while opening view.
ACCEPTED BUT PARSED INCORRECTLY
When we are setting the value in a system variable,
We can set it like
set sys_var="Iden1.Iden2"; //1
set sys_var='Iden1.Iden2'; //2
set sys_var=Iden1.Iden2; //3
set sys_var=.ident1.ident2; //4
set sys_var=`Iden1.Iden2`; //5
While parsing, for case 1(when ANSI_QUOTES is enable) and 2,
we will take as string literal(we will make item of type Item_string).
for case 3 & 4, taken as Item_field, where Iden1 is a table name and
iden2 is a field name.
for case 5, again Item_field type, where iden1.iden2 is taken as
field name.
Now in case 1, when we are assigning some value to system variable
(which can take string or enumerate type data), we are setting only
field part.
This means only iden2 value will be set for system variable. This
result in wrong result.
Solution:
(for string type) We need to Document that we are not allowed to set
system variable which takes string as identifier, otherwise result
in unexpected behaviour.
(for enumerate type)
if we pass iden1.iden2, we will give an error ER_WRONG_TYPE_FOR_VAR
(Incorrect argument type to variable).
mysql-test/suite/sys_vars/t/general_log_file_basic.test:
Earlier we used to give ER_WRONG_VALUE_FOR_VAR error, but in the patch of
(Bug32748-Inconsistent handling of assignments to general_log_file/slow_query_log_file)
they quoted this line.But i am not able to find any relation of this with the changes of
patch. So i think We should give error in this case.
mysql-test/suite/sys_vars/t/slow_query_log_file_basic.test:
Earlier we used to give ER_WRONG_VALUE_FOR_VAR error, but in the patch of
(Bug32748-Inconsistent handling of assignments to general_log_file/slow_query_log_file)
they quoted this line.But i am not able to find any relation of this with the changes of
patch. So i think We should give error in this case.
ACCEPTED BUT PARSED INCORRECTLY
When we are setting the value in a system variable,
We can set it like
set sys_var="Iden1.Iden2"; //1
set sys_var='Iden1.Iden2'; //2
set sys_var=Iden1.Iden2; //3
set sys_var=.ident1.ident2; //4
set sys_var=`Iden1.Iden2`; //5
While parsing, for case 1(when ANSI_QUOTES is enable) and 2,
we will take as string literal(we will make item of type Item_string).
for case 3 & 4, taken as Item_field, where Iden1 is a table name and
iden2 is a field name.
for case 5, again Item_field type, where iden1.iden2 is taken as
field name.
Now in case 1, when we are assigning some value to system variable
(which can take string or enumerate type data), we are setting only
field part.
This means only iden2 value will be set for system variable. This
result in wrong result.
Solution:
(for string type) We need to Document that we are not allowed to set
system variable which takes string as identifier, otherwise result
in unexpected behaviour.
(for enumerate type)
if we pass iden1.iden2, we will give an error ER_WRONG_TYPE_FOR_VAR
(Incorrect argument type to variable).
Problem was that we used cache_table in some cases where it was not initialized
mysql-test/r/func_group.result:
Added test case
mysql-test/t/func_group.test:
Added test case
sql/item.cc:
Don't use cached_table if not set
sql/item_sum.cc:
Don't use cached_table
The field JOIN::select_lex->where should be updated after the call
of remove_eq_conds() in the function make_join_statistics(). This
matters for subselects.
on server shutdown after SELECT with CONVERT_TZ
It's wrong to return my_empty_string from val_str().
Removing my_empty_string. Using make_empty_result() instead.
INSTALL PLUGIN
There was mixed lock order between LOCK_plugin, LOCK_global_system_variables
and LOCK_system_variables_hash. This patch ensures that write-lock on
LOCK_system_variables_hash doesn't intersect with LOCK_plugin.
Fixed by moving initialization/deinitialization of plugin options from
plugin_add()/plugin_del() to plugin_initialize()/plugin_deinitalize().
So that plugin options are handled without protection of LOCK_plugin.
if two threads were calling mi_assign_to_key_cache() for the same table,
one could change share->key_cache while the other was having
share->key_cache->op_lock locked. The other thread would crash then,
trying to unlock share->key_cache->op_lock (because it would be a different mutex).
fixed by caching the value of share->key_cache in a local variable. The thread can still
call flush_key_blocks() for an unassigned keycache, but it's harmless.
Old code in create_tmp_table(), that created an extra one-byte field (recinfo)
before every NULL-able grouping field (Field) in the tmp table, did not actually work.
Because the matching code in end_update(), that was supposed to update this byte,
was using a wrong offset, updating the first byte of the Field, not a byte before it.
Normally this wasn't an issue, because the Field value (written later in end_update)
was overwriting this byte anyway. But in this bug the Field was Field_null, with zero
length, so end_update() was overwriting the first byte of the following field.
And the following field was not-nullable constant, which was stored only once in
create_tmp_table and never updated later.
Fixed by removing the code that didn't do any useful work anyway.
Added variable "OLD_MODE" that can be used to turn off the new behavior
mysql-test/r/insert.result:
Added test case
mysql-test/r/mysqld--help.result:
Added old_mode
mysql-test/suite/sys_vars/r/old_mode_basic.result:
Added testing of new variable
mysql-test/suite/sys_vars/t/old_mode_basic.test:
Added testing of new variable
mysql-test/t/insert.test:
Added test case
sql/sql_class.h:
Added bit flags for OLD_MODE
sql/sql_insert.cc:
Disable duplicate key warnings for INSERT IGNORE of OLD_MODE NO_DUP_KEY_WARNINGS_WITH_IGNORE is used
sql/sql_show.cc:
Don't show progress reporting on SHOW PROCESSLIST if OLD_MODE NO_PROGRESS_INFO is used
sql/sys_vars.cc:
Added OLD_MODE
Added test cases
mysql-test/r/mysql_tzinfo_to_sql_symlink.result:
Updated results
mysql-test/std_data/zoneinfo/garbage:
test file
mysql-test/std_data/zoneinfo/ignored.tab:
test file
mysql-test/t/mysql_tzinfo_to_sql_symlink.test:
Added test cases for all options
sql/tztime.cc:
Better error messages.
Fixed wrong place for 'continue'
MDEV-5337: Wrong result in mariadb 5.5.32 with ORDER BY + LIMIT when
index_condition_pushdown=on
- in test_if_skip_sort_order(), correct the condition under which
we have the code that restores the previously pushed index condition.
The crash happened because Item_func_monthname was derived from
Item_func_month, so Item_func_monthname::is_null() did not work fine.
Backporting a change from 5.5: Item_func_monthname is now derived from
Item_str_func.
Main fix was to not cache derivied tables as they may be temporary tables that are deleted before the next query.
This was a bit tricky as Item_field::fix_fields depended on cached_tables to be set to resolve some columns.
mysql-test/r/sp-bugs.result:
Added test case
mysql-test/t/sp-bugs.test:
Added test case
sql/item.cc:
Fixed fix_outer_field to handle case where found field did not have in cached_table
Idea is that if cached_table is not avaliable, use from_field->table->pos_in_table_list instead
sql/records.cc:
Also accept INTERNAL_TMP_TABLE for memmap
sql/sql_base.cc:
More DBUG_PRINT
Fixed that setup_natural_join_row_types() is not run twice.
Original code modified context->first_name_resolution_table also for second executions.
This was wrong as this could give wrong results if some joins had been optimized away between calls.
sql/sql_derived.cc:
Mark derived tables as internal temporary tables (INTERNAL_TMP_TABLE), not as NON_TRANSACTIONAL_TMP_TABLE.
This is more correct as the tables are not visible by the end user.
sql/sql_insert.cc:
Reset pos_in_table_list before calling fix_fields.
One of the consequences of the change of not caching all generated tables in Item_ident is that
pos_in_table_list needs to be correct in calls to fix_fields.
sql/sql_lex.cc:
More DBUG_PRINT
sql/sql_parse.cc:
Don't cache derivied tables as they may be temporary tables that are deleted before the next query
sql/sql_select.cc:
Reset table_vector. This was required as some code checked the vector to see if temporary tables had already been created.
sql/table.cc:
Mark tables with field translations as cacheable (as these will not disapper between stmt executions.
- convert_subq_to_sj() must connect child select's tables into
parent select's TABLE_LIST::next_local chain.
- The problem was that it took child's leaf_tables.head() which
is different. This could cause certain tables (in this bug's case,
child select's non-merged semi-join) not to be present in
TABLE_LIST::next_local chain. Which would cause non-merged semi-join
not to be initialized in setup_tables(), which would lead to
NULL pointer dereference.
- convert_subq_to_sj() must connect child select's tables into
parent select's TABLE_LIST::next_local chain.
- The problem was that it took child's leaf_tables.head() which
is different. This could cause certain tables (in this bug's case,
child select's non-merged semi-join) not to be present in
TABLE_LIST::next_local chain. Which would cause non-merged semi-join
not to be initialized in setup_tables(), which would lead to
NULL pointer dereference.
THD::thd->activate_stmt_arena_if_needed() should be used to temporary activating statement arena instead of direct usage of THD::set_n_backup_active_arena() because possible such scenario:
1) func1 saves current arena and activates copy1 of statement arena
2) func2 saves copy1 of statement arena setup by func1 and activates copy2
3) some changes made for copy 2
4) func2 stores changed copy2 back to statenet arena and activates copy1
5) func1 store unchanged copy1 back to statemnt arena (rewrite changed copy 2 so changes become lost) and activates arena which was before.
After table->file->add_index() in mysql_alter_table() the table in the engine
has the intermediate temporary structure, it's neither the original nor the
final table structure (it'll be final after successful table->file->drop_index()
call). So, when add_index() fails with a unique key violation, we cannot simply
get the failed key number and easily map it to the key name and key structure via
table->key_info[key_no].
For now we'll create this "intermediate temporary structure", emulating InnoDB
internal rules.
This bug and the fix will go away in 10.0 that uses completely different online
alter table code.
mysql-test/t/alter_table_trans.test:
mdev:5406
mysql_upgrade --help now also prints out --default options and variable values.
mysql_upgrade now prints permission errors.
mysql_upgrade doesn't print some non essential info if --silent is used.
Added handler error message about incompatible versions
Fixed that mysqlbug and mysql_install_db have the executable flag set.
Removed executable flag for some non executable files.
Changed in mysql_install_db askmonty.org to mariadb.com.
Ensured that all client executables prints --default options the same way.
Allow REPAIR ... USE_FRM for old .frm files if the are still compatible.
Extended shown error for storage engine messages.
client/mysql.cc:
print_defaults() should be first (as in all other programs)
client/mysql_upgrade.c:
--help now also prints out --default options and variable values
Print out error if wrong permissions
Don't print info if --silent
client/mysqladmin.cc:
print_defaults() should be first (as in all other programs)
client/mysqlbinlog.cc:
Added print_defaults() to --help
client/mysqlcheck.c:
Added empty line in --help
client/mysqlimport.c:
Added empty line in --help
client/mysqlshow.c:
Made --help compatible
client/mysqlslap.c:
Made --help compatible
client/mysqltest.cc:
Added print_defaults() to --help
include/handler_ername.h:
Added handler error message
include/my_base.h:
Added handler error message
mysql-test/r/mysql_upgrade.result:
Updated results
mysql-test/r/repair.result:
Added test case for better error messages
mysql-test/std_data/host_old.MYD:
Added test case for better error messages
mysql-test/std_data/host_old.MYI:
Added test case for better error messages
mysql-test/std_data/host_old.frm:
Added test case for better error messages
mysql-test/t/repair.test:
Added test case for better error messages
mysys/my_handler_errors.h:
Added handler error message
scripts/CMakeLists.txt:
Fixed that mysqlbug and mysql_install_db have the executable flag set
scripts/mysql_install_db.sh:
askmonty.org -> mariadb.com
sql/ha_partition.cc:
Sometimes table_type() can be called for errors even if partition didn't manage to open any files
sql/handler.cc:
Write clear text for not handled, but defined error messages.
sql/share/errmsg-utf8.txt:
Extended shown error for storage engine messages
sql/sql_admin.cc:
Allow REPAIR ... USE_FRM for old .frm files if the are still compatible
storage/myisam/ha_myisam.cc:
Use new error message
