------------------------------------------------------------
revno: 3258
committer: Jon Olav Hauglid <jon.hauglid@oracle.com>
branch nick: mysql-trunk-bug12663165
timestamp: Thu 2011-07-14 10:05:12 +0200
message:
Bug#12663165 SP DEAD CODE REMOVAL DOESN'T UNDERSTAND CONTINUE HANDLERS
When stored routines are loaded, a simple optimizer tries to locate
and remove dead code. The problem was that this dead code removal
did not work correctly with CONTINUE handlers.
If a statement triggers a CONTINUE handler, the following statement
will be executed after the handler statement has completed. This
means that the following statement is not dead code even if the
previous statement unconditionally alters control flow. This fact
was lost on the dead code removal routine, which ended up with
removing instructions that could have been executed. This could
then lead to assertions, crashes and generally bad behavior when
the stored routine was executed.
This patch fixes the problem by marking as live code all stored
routine instructions that are in the same scope as a CONTINUE handler.
Test case added to sp.test.
If init_command was incorrect, we couldn't let users execute
queries, but we couldn't report the issue to the client either
as it does not expect error messages before even sending a
command. Thus, we simply disconnected them without throwing
a clear error.
We now go through the proper sequence once (without executing
any user statements) so we can report back what the problem
is. Only then do we disconnect the user.
As always, root remains unaffected by this as init_command is
(still) not executed for them.
CREATE TABLE bug13510739 (c INTEGER NOT NULL, PRIMARY KEY (c)) ENGINE=INNODB;
INSERT INTO bug13510739 VALUES (1), (2), (3), (4);
DELETE FROM bug13510739 WHERE c=2;
HANDLER bug13510739 OPEN;
HANDLER bug13510739 READ `primary` = (2);
HANDLER bug13510739 READ `primary` NEXT; <-- crash
The bug is that in the particular testcase row_search_for_mysql() picked up
a delete-marked record and quit, leaving the cursor non-positioned state and
on the subsequent 'get next' call the code crashed because of the
non-positioned cursor.
In row0sel.cc (line numbers from mysql-trunk):
4653 if (rec_get_deleted_flag(rec, comp)) {
...
4679 if (index == clust_index && unique_search) {
4680
4681 err = DB_RECORD_NOT_FOUND;
4682
4683 goto normal_return;
4684 }
it quit from here, not storing the cursor position.
In contrast, if the record=2 is not found at all (e.g. sleep(1) after DELETE
to let the purge wipe it away completely) then 'get = 2' does find record=3
and quits from here:
4366 if (0 != cmp_dtuple_rec(search_tuple, rec, offsets)) {
...
4394 btr_pcur_store_position(pcur, &mtr);
4395
4396 err = DB_RECORD_NOT_FOUND;
4397 #if 0
4398 ut_print_name(stderr, trx, FALSE, index->name);
4399 fputs(" record not found 3\n", stderr);
4400 #endif
4401
4402 goto normal_return;
Another fix could be to extend the condition on line 4366 to hold only if
seach_tuple matches rec AND if rec is not delete marked.
Notice that in the above test case if we wait about 1 second somewhere after
DELETE and before 'get = 2', then the testcase does not crash and returns 4
instead. Not sure if this is the correct behavior, but this bugfix removes
the crash and makes the code return what it also returns in the non-crashing
case (if rec=2 is not found during 'get = 2', e.g. we have sleep(1) there).
Approved by: Marko (http://bur03.no.oracle.com/rb/r/863/)
The counter handler_read_key (SSV::ha_read_key_count) is incremented
incorrectly.
The mysql server maintains a per thread system_status_var (SSV)
object. This object contains among other things the counter
SSV::ha_read_key_count. The purpose of this counter is to measure the
number of requests to read a row based on a key (or the number of
index lookups).
This counter was wrongly incremented in the
ha_innobase::innobase_get_index(). The fix removes
this increment statement (for both innodb and innodb_plugin).
The various callers of the innobase_get_index() was checked to
determine if anybody must increment this counter (if they first call
innobase_get_index() and then perform an index lookup). It was found
that no caller of innobase_get_index() needs to worry about the
SSV::ha_read_key_count counter.
SMALL KEY CACHE
The server crashed on division by zero because the key cache was not
initialized and the block length was 0 which was used in a division.
The fix was to not allow CACHE INDEX if the key cache was not initiallized.
Thus never try LOAD INDEX INTO CACHE for an uninitialized key cache.
Also added some windows files/directories to .bzrignore.
AND HANG IN SHOW TABLE STATUS.
ISSUE: Table corruption due to concurrent queries.
Different threads running insert and check
query leads to table corruption. Not properly locked,
rows are inserted in between check query.
SOLUTION: In check query mutex lock is acquired
for a longer time to handle concurrent
insert and check query.
NOTE: Additionally we backported the fix for CHECKSUM
issue(bug#11758979).
rb://816
approved by: Marko Makela
The title is misleading. This bug was actually introduced by
bug 12635227 and was unearthed by a later optimization.
We need to free buf_page_t structs that we are allocating using
malloc() at shutdown.
The bug was accidentally fixed by fixing
Bug#11759688 52020: InnoDB can still deadlock on just INSERT...ON DUPLICATE KEY
a.k.a. the reintroduction of
Bug#7975 deadlock without any locking, simple select and update
a.k.a. Bug#7975 deadlock without any locking, simple select and update
Bug#7975 was reintroduced when the storage engine API was made
pluggable in MySQL 5.1. Instead of looking at thd->lex directly, we
rely on handler::extra(). But, we were looking at the wrong extra()
flag, and we were ignoring the TRX_DUP_REPLACE flag in places where we
should obey it.
innodb_replace.test: Add tests for hopefully all affected statement
types, so that bug should never ever resurface. This kind of tests
should have been added when fixing Bug#7975 in MySQL 5.0.3 in the
first place.
rb:806 approved by Sunny Bains
This was an attempt to address problems with the Bug#12612184 fix.
Even with this follow-up fix, crash recovery can be broken.
Let us fix the bug later.
In the ON UPDATE CASCADE clause of FOREIGN KEY constraints, the
calculated update vector was not fully initialized. This bug was
introduced in the InnoDB Plugin when implementing support for
ROW_FORMAT=DYNAMIC.
Additionally, the data type information was not initialized, but
apparently it has never been needed in this case. Nevertheless, it is
not good programming practice to pass uninitialized values around.
calc_row_difference(): Declare the update field uninitialized in
Valgrind. Copy the data type information as well, except when the
field is SQL NULL. In the built-in InnoDB, initialize
ufield->extern_storage = FALSE (an initialization bug that had gone
unnoticed this far). The InnoDB Plugin and later have this flag to
dfield_t and have always initialized it properly.
row_ins_cascade_calc_update_vec(): Reduce the scope of some
pointers. Initialize orig_len. (This caused the bug in InnoDB Plugin
and later.)
row_ins_foreign_check_on_constraint(): Simplify a condition. Declare
the update vector uninitialized.
rb:771 approved by Jimmy Yang
PARENT FOR OTHER ONE
Do not try to lookup key_nr'th key in 'table' because there may not be such
a key there. key_nr is the number of the key in the _child_ table name, not
in the parent table.
Instead just print the fields of the record that are covered by the first key
defined on the parent table.
This bug gets a better fix in MySQL 5.6, which is too risky for 5.1 and 5.5.
Approved by: Jon Olav Hauglid (via IM)
USING MYISAM_USE_MMAP ON WINDOWS
When OPTIMIZE/REPAIR TABLE is switching to new data file,
old data file is removed while memory mapping is still
active.
With 5.1 implementation of nt_share_delete() it is not
permitted to remove mmaped file.
This fix disables memory mapping for mi_repair() operations.
Buffer over-run on all platforms, crash on windows, wrong result on other platforms,
when rounding numbers which start with 999999999 and have
precision = 9 or 18 or 27 or 36 ...
Problematic query:
insert ignore into `t1_federated` (`c1`) select `c1` from `t1_local` a
where not exists (select 1 from `t1_federated` b where a.c1 = b.c1);
When this query is killed in another connection it could lead to crash.
The problem is follwing:
An attempt to obtain table statistics for subselect table in killed query
fails with an error. So JOIN::optimize() for subquery is failed but
it does not prevent further subquery evaluation.
At the first subquery execution JOIN::optimize() is called
(see subselect_single_select_engine::exec()) and fails with
an error. 'executed' flag is set to TRUE and it prevents
further subquery evaluation. At the second call
JOIN::optimize() does not happen as 'JOIN::optimized' is TRUE
and in case of uncacheable subquery the 'executed' flag is set
to FALSE before subquery evaluation. So we loose 'optimize stage'
error indication (see subselect_single_select_engine::exec()).
In other words 'executed' flag is used for two purposes, for
error indication at JOIN::optimize() stage and for an
indication of subquery execution. And it seems it's wrong
as the flag could be reset.
1 - If a user had SHOW VIEW and SELECT privileges on a view and
this view was referencing another view, EXPLAIN SELECT on the outer
view (that the user had privileges on) could reveal the structure
of the underlying "inner" view as well as the number of rows in
the underlying tables, even if the user had privileges on none of
these referenced objects.
This happened because we used DEFINER's UID ("SUID") not just for
the view given in EXPLAIN, but also when checking privileges on
the underlying views (where we should use the UID of the EXPLAIN's
INVOKER instead).
We no longer run the EXPLAIN SUID (with DEFINER's privileges).
This prevents a possible exploit and makes permissions more
orthogonal.
2 - EXPLAIN SELECT would reveal a view's structure even if the user
did not have SHOW VIEW privileges for that view, as long as they
had SELECT privilege on the underlying tables.
Instead of requiring both SHOW VIEW privilege on a view and SELECT
privilege on all underlying tables, we were checking for presence
of either of them.
We now explicitly require SHOW VIEW and SELECT privileges on
the view we run EXPLAIN SELECT on, as well as all its
underlying views. We also require SELECT on all relevant
tables.
SYSTEM VARIABLE NAME SQL_MAX_JOIN_SI
BACKGROUND:
ER_TOO_BIG_SELECT refers to SQL_MAX_JOIN_SIZE, which is the
old name for MAX_JOIN_SIZE.
FIX:
Support for old name SQL_MAX_JOIN_SIZE is removed in MySQL 5.6
and is renamed as MAX_JOIN_SIZE.So the errmsg.txt
and mysql.cc files have been updated and the corresponding result
files have also been updated.
CREATE_TIME IN INFORMATION_SC
It was impossible to determine MEMORY table creation time,
since it wasn't stored/exposed.
With this patch creation time is saved and it is available via
I_S.TABLES.CREATE_TIME.
Note: it was decided that additional analysis is required before
implementing UPDATE_TIME. Thus this patch doesn't store UPDATE_TIME.
Added 'innodb_file_format_check' as variable to ignore change to.
Tests that had to restore this amended
Two tests assumed it to be Antelope, make sure these run on a freshly
started server
For 5.5, apparently innodb_file_format_max is the one to ignore
The problem occurred when indexes are added between the time that an
UNDO record is created and the time that the purge thread comes around
and deletes the old secondary index entries. The purge thread would
hit an assert when trying to build a secondary index entry for
searching. The problem was that the old value of those fields were not
in the UNDO record since they were not part of an index when the UPDATE
occured.
A test case was added to innodb-index.test.
FULLTEXT INDEXES
myisamchk may create incorrect fulltext index for compressed
tables. Incorrect data pointer size was used while creating
fulltext index.
Call handle_error() instead of die() when evaluating these
Must remember "current command" with link to errors to ignore
Added test cases to mysqltest.test
