Commit graph

71420 commits

Author SHA1 Message Date
unknown
3d7f52255b BUG #13625278 - PB2 SHOULD PROVIDE MORE USEFUL INFORMATION FOR TIMEOUTS 2013-02-06 13:02:14 +05:30
unknown
1e4aaba5ed Merge from mysql-5.1.68-release 2013-02-05 20:47:45 +01:00
unknown
a2be7d26a8 BUG #13625278 - PB2 SHOULD PROVIDE MORE USEFUL INFORMATION FOR TIMEOUTS 2013-02-05 11:58:21 +05:30
unknown
ddb60a719b Bug #16190704: MTR STILL LOSES THE FAILED RUN LOGS AT RETRY-FAIL 2013-02-04 20:25:30 +05:30
Mattias Jonsson
2df2e2617c post-push test result update for bug#14521864. 2013-02-04 14:09:48 +01:00
Venkatesh Duggirala
c179355f5d BUG#16247322-MTR NOT RUNNING SYS_VARS TEST SUITE FOR 5.1
Null merge from mysql-5.1
2013-02-08 16:36:47 +05:30
Venkatesh Duggirala
ae04fc7c5d BUG#16247322-MTR NOT RUNNING SYS_VARS TEST SUITE FOR 5.1
Null merge from mysql-5.1
2013-02-08 15:42:36 +05:30
Marko Mäkelä
bf4c0a1a46 Merge mysql-5.1 to mysql-5.5. 2013-02-08 09:33:21 +02:00
Igor Solodovnikov
39025d2a61 Null-merge from mysql-5.1 2013-02-07 19:46:45 +02:00
Tor Didriksen
b13d0a093d merge 5.1 => 5.5 2013-02-07 17:08:59 +01:00
Venkatesh Duggirala
506b40cd56 Bug #16247322 MTR NOT RUNNING SYS_VARS TEST SUITE FOR 5.1
Null-Merge from mysql-5.5
2013-02-07 17:27:32 +05:30
unknown
6f83811d25 Bug#16263506 - INNODB; USE ABORT() ON ALL PLATFORMS INSTEAD OF
DEREFERENCING UT_DBG_NULL_PTR
The abort() call is standard C but InnoDB only uses it in GCC
environments.  UT_DBG_USE_ABORT is not defined the code crashed
by dereferencing a null pointer instead of calling abort().
Other code throughout MySQL including ndb, sql, mysys and other
places call abort() directly.

This bug also affects innodb.innodb_bug14147491.test which fails
randomly on windows because of this issue. 

Approved by marko in http://rb.no.oracle.com/rb/r/1936/
2013-02-06 13:49:56 -06:00
Ravinder Thakur
6823ac913e Bug#14711808 MSI INSTALLATION / UPGRADE CAN CORRUPT EXISTING INSTALLATION
Currently MySQL MSI installer on Windows installs MySQL in 
"per user" mode. It means that if a Windows machine has 
multiple users, they each can install MySQL independently. 
However the default path of MySQL is "C:\Program Files (x86)\MySQL\"
and when two users install MySQL on same machine, the installation
by second user just overwrites the MySQL files. This default shared 
location leads to the issue where if the second user uninstalls MySQL,
the installation files are removed for the first user as well.

In this fix, we are now making the default installation "per machine".
It means that when MySQL is installed with defaults options, all
users can see the shortcuts for MySQL in start menu(since installations 
is for all users). Also when any user relaunches the installer, it will 
consider that action uninstallation rather than installation for that user.

There are command line options in installer that can be used to undo the
"per machine" installation but will not consider that scenario.MySQL 
is a server product and it does not make a lot of sense to install it
differently for each user.
2013-02-06 13:52:32 +05:30
unknown
5948623ed3 13625278 5.1 => 5.5 2013-02-06 13:04:41 +05:30
Hery Ramilison
67a697b7d8 Upmerge of the 5.1.68 build 2013-02-05 21:29:49 +01:00
unknown
a6a20c11dc Merge from mysql-5.5.30-release 2013-02-05 10:50:02 +01:00
unknown
c8738c1f71 13625278 5.1=> 5.5 2013-02-05 13:42:56 +05:30
Thayumanavar
e15a51363d BUG#16196591 - CLIENTS CANNOT CONNECT TO MYSQL
PROBLEM:
When large number of connections are continuously made
with wait_timeout of 600 seconds for  some hours, some
connections remain after wait_timeout expired and also
new connections get struck under the configuration and
the scenario reported in bug#16196591.
FIX:
The cause of this bug is the issue identified  and fixed in
the BUG#16088658 in 5.6.Also LOCK_thread_count contention 
issue fixed in BUG#15921866 in 5.6 need to be in 5.5 as 
well. Since the issue is not reproducible, it has been
verified at customer configuration the issue could not
be reproduced after a 48-hour test with a non-debug build               
which includes the above two fixes backported.
2013-02-05 11:06:38 +05:30
unknown
f8eea3b3c4 16190704 5.1 => 5.5 nullmerge 2013-02-04 20:41:25 +05:30
Inaam Rana
50c27a1492 Bug#16249505 INNODB REPORTS THAT IT'S GOING TO WAIT FOR I/O BUT THE
I/O IS ASYNC

rb://1934
approved by: Mikael Ronstrom (over email)
    
When submitting AIO read request don't signal that the thread is
about to wait on DISKIO
2013-02-01 09:47:16 -05:00
unknown
49e4ed1fde BUG #16190704 - MTR STILL LOSES THE FAILED RUN LOGS AT RETRY-FAIL 2013-02-01 19:53:20 +05:30
Nisha Gopalakrishnan
8500944765 BUG#16207679: MISSING ERROR WHEN RESIGNAL TO MYSQL_ERROR=5
Analysis:
--------

As part of the fix for Bug#11757464, the 'out of memory' error
condition was not pushed to the diagnostic area as it requires
memory allocation. However in cases of SIGNAL/RESIGNAL 'out of
memory' error, the server may not be out of memory. Hence it
would be good to report the error in such cases.

Fix:
---

Push only non fatal 'out of memory' errors to the diagnostic area.
Since SIGNAL/RESIGNAL of 'out of memory' error may not be fatal,
the error is reported.
2013-02-01 09:49:27 +05:30
Gleb Shchepa
dff10afb20 Bug #11827369: ASSERTION FAILED: !THD->LEX->CONTEXT_ANALYSIS_ONLY
Manual up-merge from 5.1 to 5.5.
2013-01-31 09:13:42 +04:00
Gleb Shchepa
7ebfe30b53 Bug #11827369: ASSERTION FAILED: !THD->LEX->CONTEXT_ANALYSIS_ONLY
Some queries with the "SELECT ... FROM DUAL" nested subqueries
failed with an assertion on debug builds.
Non-debug builds were not affected.

There were a few different issues with similar assertion
failures on different queries:

1. The first problem was related to the incomplete propagation
of the "non-constant" item status from underlying subquery
items to the outer item tree: in some cases non-constants were
interpreted as constants and evaluated at the preparation stage
(val_int() calls withing fix_fields() etc).

Thus, the default implementation of Item_ref::const_item() from
the Item parent class didn't take into account the "const_item"
status of the referenced item tree -- it used the insufficient
"used_tables() == 0" check instead. This worked in most cases
since our "non-constant" functions like RAND() and SLEEP() set
the RAND_TABLE_BIT in the used table map, so they aren't
non-constant from Item_ref's "point of view". However, the
"SELECT ... FROM DUAL" subquery may have an empty map of used
tables, but at the same time subqueries are never "constant" at
the context analysis stage (preparation, view creation etc).
So, the non-contantness of such subqueries was missed.

Fix: the Item_ref::const_item() function has been overloaded to
take into account both (*ref)->const_item() status and tricky
Item_ref::used_tables() return values, since the only
(*ref)->const_item() call is not enough there.

2. In some cases instead of the const_item() call we check a
value of the Item::with_subselect field to recognize items
with nested subqueries. However, the Item_ref class didn't
propagate this value from the referenced item tree.

Fix: Item::has_subquery() and Item_ref::has_subquery()
functions have been backported from 5.6. All direct
references to the with_subselect fields of nested items have
been replaced with the has_subquery() function call.

3. The Item_func_regex class didn't propagate with_subselect
as well, since it overloads the Item_func::fix_fields()
function with insufficient fix_fields() implementation.

Fix: the Item_func_regex::fix_fields() function has been
modified to gather "constant" statuses from inner items.

4. The Item_func_isnull::update_used_tables() function has
a special branch for the underlying item where the maybe_null
value is false: in this case it marks the Item_func_isnull
as a "const_item" and sets the cached_value to false.
However, the Item_func_isnull::val_int() was not in sync with
update_used_tables(): it didn't take into account neither
const_item_cache nor cached_value for the case of
"args[0]->maybe_null == false optimization".
As far as such an Item_func_isnull has "const_item() == true",
it's ok to call Item_func_isnull::val_int() etc from outer
items on preparation stage. In this case the server tried to
call Item_func_isnull::args[0]->isnull(), and if the args[0]
item contained a nested not-nullable subquery, it failed
with an assertion.

Fix: take the value of Item_func_isnull::const_item_cache into
account in the val_int() function.

5. The auxiliary Item_is_not_null_test class has a similar
optimization in the update_used_tables() function as the
Item_func_isnull class has, and the same issue in the val_int()
function.
In addition to that the Item_is_not_null_test::update_used_tables()
doesn't update the const_item_cache value, so the "maybe_null"
optimization is useless there. Thus, we missed some optimizations
of cases like these (before and after the fix):
  <  <is_not_null_test>(a),
  ---
  >  <cache>(<is_not_null_test>(a)),
or
  < having (<is_not_null_test>(a) and <is_not_null_test>(a))
  ---
  > having 1
etc.

Fix: update Item_is_not_null_test::const_item_cache in
update_used_tables() and take in into account in val_int().
2013-01-31 08:46:30 +04:00
Yasufumi Kinoshita
4dcd030420 merge to mysql-5.5 from mysql-5.1 2013-01-31 12:45:08 +09:00
Yasufumi Kinoshita
c3d2803c43 Bug #16220051 : INNODB_BUG12400341 FAILS ON VALGRIND WITH TOO MANY ACTIVE CONCURRENT TRANSACTION
innodb_bug12400341.test is disabled for valgrind daily test.
It might be affected by the previous test's undo slots existing,
because of slower execution.
2013-01-31 12:42:43 +09:00
Chaithra Gopalareddy
dbd25312fe Bug#14096619: UNABLE TO RESTORE DATABASE DUMP
Backport of fix for Bug#13581962

mysql-test/r/cast.result:
  Added test result for Bug#13581962,Bug#14096619
mysql-test/r/ctype_utf8mb4.result:
  Added test result for Bug#13581962,Bug#14096619
mysql-test/t/cast.test:
  Added test case for Bug#13581962,Bug#14096619
mysql-test/t/ctype_utf8mb4.test:
  Added test case for Bug#13581962,Bug#14096619
sql/item_func.h:
  limit max length by MY_INT64_NUM_DECIMAL_DIGITS
2013-01-31 07:06:30 +05:30
Chaithra Gopalareddy
e1ee9581cb Bug#14096619: UNABLE TO RESTORE DATABASE DUMP
Backport of Bug#13581962

mysql-test/r/cast.result:
  Added test result for Bug#13581962,Bug#14096619
mysql-test/t/cast.test:
  Added test case for Bug#13581962,Bug#14096619
sql/item_func.h:
  limit max length by MY_INT64_NUM_DECIMAL_DIGITS
2013-01-31 06:39:15 +05:30
Mattias Jonsson
d92a7cb76a Bug#14521864: MYSQL 5.1 TO 5.5 BUGS PARTITIONING
Due to an internal change in the server code in between 5.1 and 5.5
(wl#2649) the hash function used in KEY partitioning changed
for numeric and date/time columns (from binary hash calculation
to character based hash calculation).

Also enum/set changed from latin1 ci based hash calculation to
binary hash between 5.1 and 5.5. (bug#11759782).

These changes makes KEY [sub]partitioned tables on any of
the affected column types incompatible with 5.5 and above,
since the calculation of partition id differs.

Also since InnoDB asserts that a deleted row was previously
read (positioned), the server asserts on delete of a row that
is in the wrong partition.

The solution for this situation is:

1) The partitioning engine will check that delete/update will go to the
partition the row was read from and give an error otherwise, consisting
of the rows partitioning fields. This will avoid asserts in InnoDB and
also alert the user that there is a misplaced row. A detailed error
message will be given, including an entry to the error log consisting
of both table name, partition and row content (PK if exists, otherwise
all partitioning columns).


2) A new optional syntax for KEY () partitioning in 5.5 is allowed:
[SUB]PARTITION BY KEY [ALGORITHM = N] (list_of_cols)
Where N = 1 uses the same hashing as 5.1 (Numeric/date/time fields uses
binary hashing, ENUM/SET uses charset hashing) N = 2 uses the same
hashing as 5.5 (Numeric/date/time fields uses charset hashing,
ENUM/SET uses binary hashing). If not set on CREATE/ALTER it will
default to 2.

This new syntax should probably be ignored by NDB.


3) Since there is a demand for avoiding scanning through the full
table, during upgrade the ALTER TABLE t PARTITION BY ... command is
considered a no-op (only .frm change) if everything except ALGORITHM
is the same and ALGORITHM was not set before, which allows manually
upgrading such table by something like:
ALTER TABLE t PARTITION BY KEY ALGORITHM = 1 () or
ALTER TABLE t PARTITION BY KEY ALGORITHM = 2 ()


4) Enhanced partitioning with CHECK/REPAIR to also check for/repair
misplaced rows. (Also works for ALTER TABLE t CHECK/REPAIR PARTITION)

CHECK FOR UPGRADE:
If the .frm version is < 5.5.3
and uses KEY [sub]partitioning
and an affected column type
then it will fail with an message:
KEY () partitioning changed, please run:
ALTER TABLE `test`.`t1`  PARTITION BY KEY ALGORITHM = 1 (a)
PARTITIONS 12
(i.e. current partitioning clause, with the addition of
ALGORITHM = 1)

CHECK without FOR UPGRADE:
if MEDIUM (default) or EXTENDED options are given:
Scan all rows and verify that it is in the correct partition.
Fail for the first misplaced row.

REPAIR:
if default or EXTENDED (i.e. not QUICK/USE_FRM):
Scan all rows and every misplaced row is moved into its correct
partitions.


5) Updated mysqlcheck (called by mysql_upgrade) to handle the
new output from CHECK FOR UPGRADE, to run the ALTER statement
instead of running REPAIR.

This will allow mysql_upgrade (or CHECK TABLE t FOR UPGRADE) to upgrade
a KEY [sub]partitioned table that has any affected field type
and a .frm version < 5.5.3 to ALGORITHM = 1 without rebuild.


Also notice that if the .frm has a version of >= 5.5.3 and ALGORITHM
is not set, it is not possible to know if it consists of rows from
5.1 or 5.5! In these cases I suggest that the user does:
(optional)
LOCK TABLE t WRITE;
SHOW CREATE TABLE t;
(verify that it has no ALGORITHM = N, and to be safe, I would suggest
backing up the .frm file, to be used if one need to change to another
ALGORITHM = N, without needing to rebuild/repair)
ALTER TABLE t <old partitioning clause, but with ALGORITHM = N>;
which should set the ALGORITHM to N (if the table has rows from
5.1 I would suggest N = 1, otherwise N = 2)
CHECK TABLE t;
(here one could use the backed up .frm instead and change to a new N
and run CHECK again and see if it passes)
and if there are misplaced rows:
REPAIR TABLE t;
(optional)
UNLOCK TABLES;
2013-01-30 17:51:52 +01:00
unknown
7aa707f233 2013-01-30 15:17:19 +01:00
unknown
16bf552e3e 2013-01-30 14:32:52 +05:30
Aditya A
db107cb36b Bug#14756795 SELECT FROM NEW INNODB I_S TABLES CRASHES SERVER
WITH --SKIP-INNODB

Description
-----------

If the server is started with skip-innodb or InnoDB otherwise fails to
start, any one of these queries will crash the server:

For (5.5) 
SELECT * FROM INFORMATION_SCHEMA.INNODB_BUFFER_PAGE;
SELECT * FROM INFORMATION_SCHEMA.INNODB_BUFFER_PAGE_LRU;
SELECT * FROM INFORMATION_SCHEMA.INNODB_BUFFER_POOL_STATS;

In (5.6+) ,following queries will also crash the server.

SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_TABLES;
SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_INDEXES;
SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_COLUMNS;
SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_FIELDS;
SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_FOREIGN;
SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_FOREIGN_COLS;
SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_TABLESTATS;
SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_DATAFILES;
SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_TABLESPACES;

FIX
----

When Innodb is not active we must prevent it from processing
these tables,so we return a warning saying that innodb is not
active.

Approved by marko (http://rb.no.oracle.com/rb/r/1891)
2013-01-30 10:53:43 +05:30
Krunal Bauskar krunal.bauskar@oracle.com
c053d055b6 - BUG#1608883: KILLING A QUERY INSIDE INNODB CAUSES IT TO EVENTUALLY CRASH
WITH AN ASSERTION
  Null merge from mysql-5.1
2013-01-30 08:27:33 +05:30
Krunal Bauskar krunal.bauskar@oracle.com
ed15e9c270 - BUG#1608883: KILLING A QUERY INSIDE INNODB CAUSES IT TO EVENTUALLY CRASH
WITH AN ASSERTION

  Correcting the build failure that was caused because of changes 
  checked-in to below mentioned revision.
  (Changes: DEBUG_SYNC_C should be disabled for innodb_plugin under
   Windows enviornment. Note: only for innodb_plugin.)

  revno: 3915
  revision-id: krunal.bauskar@oracle.com-20130114051951-ang92lkirop37431
  parent: nisha.gopalakrishnan@oracle.com-20130112054337-gk5pmzf30d2imuw7
  committer: Krunal Bauskar krunal.bauskar@oracle.com
  branch nick: mysql-5.1
  timestamp: Mon 2013-01-14 10:49:51 +0530
2013-01-30 08:17:24 +05:30
Neeraj Bisht
5a4cdc5f8e Bug#16208709 - CRASH IN GET_SEL_ARG_FOR_KEYPART ON SELECT DISTINCT
ON COL WITH COMPOSITE INDEX

This problem is caused by the patch for the bug#11751794.
While checking for the keypart covering non grouping attribute. we are not 
checking whether the root node of the SEL_ARG* tree for the index have any 
cvalue or not.

sql/opt_range.cc:
  check whether the keeypart_tree has any range tree.
2013-01-29 10:06:31 +05:30
Neeraj Bisht
265814f2ae Bug#16208709 - CRASH IN GET_SEL_ARG_FOR_KEYPART ON SELECT DISTINCT
ON COL WITH COMPOSITE INDEX

This problem is caused by the patch for the bug#11751794.
While checking for the keypart covering non grouping attribute. we are not 
checking whether the root node of the SEL_ARG* tree for the index have any 
cvalue or not.
2013-01-29 10:05:00 +05:30
Nuno Carvalho
ff0c072913 BUG#16200555: EMPTY NAME FOR USER VARIABLE IS ALLOWED AND BREAKS STATEMENT BINARY LOGGING
Merge from mysql-5.1 into mysql-5.5.
2013-01-28 19:08:50 +00:00
Nuno Carvalho
d1378565bb BUG#16200555: EMPTY NAME FOR USER VARIABLE IS ALLOWED AND BREAKS STATEMENT BINARY LOGGING
On a previous fix, user variables with zero length name were incorrectly
considered as event corruption, despite that them are allowed by server.

Fix this wrong assumption by allowing again user variables with zero
length on binary log.
2013-01-28 19:05:09 +00:00
Satya Bodapati
d63f54c67d Bug#16183892 - INNODB PURGE BUFFERING IS NOT CRASH-SAFE
With innodb_change_buffering enabled, Innodb buffers
all modifications to secondary index leaf pages when
the leaf pages are not in buffer pool.

Crash InnoDB while an IBUF_OP_DELETE is being applied.
Restart and note that the same record can be applied
again which may lead to crash.

Mark the change buffer record processed, so that it will
not be merged again in case the server crashes between
the following mtr_commit() and the subsequent mtr_commit()
of deleting the change buffer record.

Testcase: No testcase because it is difficult to get the
timing right with the two asyncronous task purge and change
buffering

Approved by Marko. rb#1893
2013-01-28 20:13:44 +05:30
Venkatesh Duggirala
3c5326f8cc Bug#16084594 USER_VAR ITEM IN 'LOAD FILE QUERY' WAS NOT
PROPERLY QUOTED IN BINLOG FILE
Merging fix from mysql-5.1
2013-01-28 14:58:55 +05:30
Venkatesh Duggirala
7e0901b97f Bug#16084594 USER_VAR ITEM IN 'LOAD FILE QUERY' WAS NOT
PROPERLY QUOTED IN BINLOG FILE
Problem: In load data file query, User variables are allowed
inside "Into_list" and "Set_list". These user variables used
inside these two lists are not properly guarded with backticks
while server is writting into binlog. Hence user variable names
like a` cannot be used in this context.

Fix: Properly quote these variables while
writting into binlog

mysql-test/r/func_compress.result:
  changing result file
mysql-test/r/variables.result:
  changing result file
mysql-test/suite/binlog/r/binlog_stm_mix_innodb_myisam.result:
  changing result file
sql/item_func.cc:
  Quote the user variable items
2013-01-28 14:41:54 +05:30
Venkatesh Duggirala
08a22ba1c9 Bug#16056813-MEMORY LEAK ON FILTERED SLAVE
Due to not resetting a member (last_added) of 
Deferred events class inside a clean up function
(Deferred_log_events::rewind), there is a memory
leak on filtered slaves.

Fix:
Resetting last_added to NULL in rewind() function.

sql/rpl_utility.cc:
  Resetting last_added to NULL to avoid memory leak
2013-01-26 15:03:01 +05:30
unknown
527c581764 2013-01-24 15:05:15 +05:30
Venkata Sidagam
26f662be1c BUG#11908153 CRASH AND/OR VALGRIND ERRORS IN FIELD_BLOB::GET_KEY_IMAGE
Backporting bug patch from 5.5 to 5.1.
This fix is applicable to BUG#14362617 as well
2013-01-24 14:56:12 +05:30
Venkata Sidagam
8be7fa51a3 Bug #11752803 SERVER CRASHES IF MAX_CONNECTIONS DECREASED BELOW
CERTAIN LEVEL

Merging from 5.1 to 5.5
2013-01-24 14:13:42 +05:30
Venkata Sidagam
776df0a366 Bug #11752803 SERVER CRASHES IF MAX_CONNECTIONS DECREASED BELOW
CERTAIN LEVEL
      
Problem description: mysqld crashes when we update the max_connections 
variable to lesser value than the number of currently open connections.
      
Analysis: The "alarm_queue.max_elements" size will be decided at the 
server start time and it will get modified if we change max_connections 
value. In the current scenario the value of "alarm_queue.max_elements" 
is decremented when the max_connections is set to 2. When updating the  
"alarm_queue.max_elements" value we are not updating "max_used_alarms" 
value. Hence, instead of getting the warning "thr_alarm queue is full" 
it is ending up in asserting the server at the time of inserting new 
elements in the queue.
      
Fix: the fix is to dynamically increase the size of the alarm_queue.
In order to do that, queue_insert_safe() should be used instead if
queue_insert().
2013-01-24 14:02:54 +05:30
Venkatesh Duggirala
f31611c4c5 BUG#14798572: REMOVE UNUSED VARIABLE BINLOG_CAN_BE_CORRUPTED
FROM MYSQL_BINLOG_SEND

As part Bug #11747416 A DISK FULL MAKES BINARY LOG CORRUPT,
reading the variable "binlog_can_be_corrupted" was removed
In the existing code the value of this variable is only set,
never read. And also this issue causing compiler warnings.
So the variable is completely redundant and should be removed.

sql/sql_repl.cc:
  Removing dead code
2013-01-24 10:35:07 +05:30
Yasufumi Kinoshita
7ebefeec6f Merge mysql-5.1 to mysql-5.5. 2013-01-23 15:00:46 +09:00
Yasufumi Kinoshita
65cb30b3b9 Bug #16089381 : POSSIBLE NUMBER UNDERFLOW AROUND CALLING PAGE_ZIP_EMPTY_SIZE()
some callers for page_zip_empty_size() ignored possibility its returning 0, and could cause underflow.

rb#1837 approved by Marko
2013-01-23 14:59:36 +09:00
Gleb Shchepa
19ea7c031d Bug #11827369: ASSERTION FAILED: !THD->LEX->CONTEXT_ANALYSIS_ONLY
Some queries with the "SELECT ... FROM DUAL" nested subqueries
failed with an assertion on debug builds.
Non-debug builds were not affected.

There were a few different issues with similar assertion
failures on different queries:

1. The first problem was related to the incomplete propagation
of the "non-constant" item status from underlying subquery
items to the outer item tree: in some cases non-constants were
interpreted as constants and evaluated at the preparation stage
(val_int() calls withing fix_fields() etc).

Thus, the default implementation of Item_ref::const_item() from
the Item parent class didn't take into account the "const_item"
status of the referenced item tree -- it used the insufficient
"used_tables() == 0" check instead. This worked in most cases
since our "non-constant" functions like RAND() and SLEEP() set
the RAND_TABLE_BIT in the used table map, so they aren't
non-constant from Item_ref's "point of view". However, the
"SELECT ... FROM DUAL" subquery may have an empty map of used
tables, but at the same time subqueries are never "constant" at
the context analysis stage (preparation, view creation etc).
So, the non-contantness of such subqueries was missed.

Fix: the Item_ref::const_item() function has been overloaded to
take into account both (*ref)->const_item() status and tricky
Item_ref::used_tables() return values, since the only
(*ref)->const_item() call is not enough there.

2. In some cases instead of the const_item() call we check a
value of the Item::with_subselect field to recognize items
with nested subqueries. However, the Item_ref class didn't
propagate this value from the referenced item tree.

Fix: Item::has_subquery() and Item_ref::has_subquery()
functions have been backported from 5.6. All direct
references to the with_subselect fields of nested items have
been with the has_subquery() function call.

3. The Item_func_regex class didn't propagate with_subselect
as well, since it overloads the Item_func::fix_fields()
function with insufficient fix_fields() implementation.

Fix: the Item_func_regex::fix_fields() function has been
modified to gather "constant" statuses from inner items.

4. The Item_func_isnull::update_used_tables() function has
a special branch for the underlying item where the maybe_null
value is false: in this case it marks the Item_func_isnull
as a "const_item" and sets the cached_value to false.
However, the Item_func_isnull::val_int() was not in sync with
update_used_tables(): it didn't take into account neither
const_item_cache nor cached_value for the case of
"args[0]->maybe_null == false optimization".
As far as such an Item_func_isnull has "const_item() == true",
it's ok to call Item_func_isnull::val_int() etc from outer
items on preparation stage. In this case the server tried to
call Item_func_isnull::args[0]->isnull(), and if the args[0]
item contained a nested not-nullable subquery, it failed
with an assertion.

Fix: take the value of Item_func_isnull::const_item_cache into
account in the val_int() function.

5. The auxiliary Item_is_not_null_test class has a similar
optimization in the update_used_tables() function as the
Item_func_isnull class has, and the same issue in the val_int()
function.
In addition to that the Item_is_not_null_test::update_used_tables()
doesn't update the const_item_cache value, so the "maybe_null"
optimization is useless there. Thus, we missed some optimizations
of cases like these (before and after the fix):
  <  <is_not_null_test>(a),
  ---
  >  <cache>(<is_not_null_test>(a)),
or
  < having (<is_not_null_test>(a) and <is_not_null_test>(a))
  ---
  > having 1
etc.

Fix: update Item_is_not_null_test::const_item_cache in
update_used_tables() and take in into account in val_int().
2013-01-23 09:51:50 +04:00