concurrent SHOW CREATE
The problem was that a SHOW CREATE TABLE statement issued inside
a transaction did not release its metadata locks at the end of the
statement execution. This happened even if SHOW CREATE TABLE is an
information statement.
The consequence was that SHOW CREATE TABLE was able to block other
connections from accessing the table (e.g. using ALTER TABLE).
This patch fixes the problem by explicitly releasing any metadata
locks taken by SHOW CREATE TABLE after the statement completes.
Test case added to show_check.test.
and reverse() function
3 problems fixed :
1. The reported problem : caused by incorrect parsing of
the file as ucs data resulting in wrong length of the parsed
string. Fixed by truncating the invalid trailing bytes
(non-complete multibyte characters) when reading from the file
2. LOAD DATA when reading from a proper UCS2 file wasn't
recognizing the new line characters. Fixed by first looking
if a byte is a new line (or any other special) character before
reading it as a part of a multibyte character.
3. When using user variables to hold the column data in LOAD
DATA the character set of the user variable was set incorrectly
to the database charset. Fixed by setting it to the charset
specified by LOAD DATA (if any).
naming scheme for tests related to functions, rename analyse.test to
func_analyse.test (test for the ANALYSE() procedure). Avoids confusion
with the ANALYZE statement (tested in analyze.test).
The problem there is that HAVING condition evaluates const
parts of condition despite the condition has references
on aggregate functions. Table t1 became const tables
after make_join_statistics and table1.pk = 1, HAVING is
transformed into MAX(1) < 7 and taken away from HAVING.
The fix is to skip evaluation of HAVING conts parts if
HAVING condition has references on aggregate functions.
Problem: Item_str_ascii_func::val_str() did not set
charset of the returned value properly.
mysql-test/include/ctype_numconv.inc
mysql-test/r/ctype_binary.result
mysql-test/r/ctype_cp1251.result
mysql-test/r/ctype_latin1.result
mysql-test/r/ctype_ucs.result
- Adding tests
sql/item_strfunc.cc
- Adding initialization of charset
Essentially, the problem is that safemalloc is excruciatingly
slow as it checks all allocated blocks for overrun at each
memory management primitive, yielding a almost exponential
slowdown for the memory management functions (malloc, realloc,
free). The overrun check basically consists of verifying some
bytes of a block for certain magic keys, which catches some
simple forms of overrun. Another minor problem is violation
of aliasing rules and that its own internal list of blocks
is prone to corruption.
Another issue with safemalloc is rather the maintenance cost
as the tool has a significant impact on the server code.
Given the magnitude of memory debuggers available nowadays,
especially those that are provided with the platform malloc
implementation, maintenance of a in-house and largely obsolete
memory debugger becomes a burden that is not worth the effort
due to its slowness and lack of support for detecting more
common forms of heap corruption.
Since there are third-party tools that can provide the same
functionality at a lower or comparable performance cost, the
solution is to simply remove safemalloc. Third-party tools
can provide the same functionality at a lower or comparable
performance cost.
The removal of safemalloc also allows a simplification of the
malloc wrappers, removing quite a bit of kludge: redefinition
of my_malloc, my_free and the removal of the unused second
argument of my_free. Since free() always check whether the
supplied pointer is null, redudant checks are also removed.
Also, this patch adds unit testing for my_malloc and moves
my_realloc implementation into the same file as the other
memory allocation primitives.
from mysql-next-mr-opt-backporting.
Bug#54515: Crash in opt_range.cc::get_best_group_min_max on
SELECT from VIEW with GROUP BY
When handling the grouping items in get_best_group_min_max, the
items need to be of type Item_field. In this bug, an ASSERT
triggered because the item used for grouping was an
Item_direct_view_ref (i.e., the group column is from a view).
The fix is to get the real_item since Item_ref* pointing to
Item_field is ok.
Problem: sha2() reported its result as BINARY
Fix:
- Inheriting Item_func_sha2 from Item_str_ascii_func
- Setting max_length via fix_length_and_charset()
instead of direct assignment.
- Adding tests
Problem: Item_copy did not set "fixed", which resulted in DBUG_ASSERT in some cases.
Fix: adding initialization of the "fixed" member
Adding tests:
mysql-test/include/ctype_numconv.inc
mysql-test/r/ctype_binary.result
mysql-test/r/ctype_cp1251.result
mysql-test/r/ctype_latin1.result
mysql-test/r/ctype_ucs.result
Adding initialization of the "fixed" member:
sql/item.h
value and NO_ZERO_DATE
The problem was that a older version of the error path for a
failed admin statement relied upon a few error conditions being
met in order to access a table handler, the first one being that
the table object pointer was not NULL. Probably due to chance,
in all cases a table object was closed but the reference wasn't
reset, the other conditions didn't evaluate to true. With the
addition of a new check on the error path, the handler started
being dereferenced whenever it was not reset to NULL, causing
problems for code paths which closed the table but didn't reset
the reference.
The solution is to reset the reference whenever a admin statement
fails and the tables are closed.
This assert checks that the server does not try to send EOF to the
client if there has been some error during processing. This to make
sure that the error is in fact sent to the client.
The problem was that any errors during processing of WHERE conditions
in HANDLER ... READ statements where not detected by the handler code.
The handler code therefore still tried to send EOF to the client,
triggering the assert. The bug was only noticeable in debug builds.
This patch fixes the problem by making sure that the handler code
checks for errors during condition processing and acts accordingly.
DROP USER
RENAME USER CURRENT_USER() ...
GRANT ... TO CURRENT_USER()
REVOKE ... FROM CURRENT_USER()
ALTER DEFINER = CURRENT_USER() EVENTbut, When these statements are binlogged, CURRENT_USER() just is binlogged
as 'CURRENT_USER()', it is not expanded to the real user name. When slave
executes the log event, 'CURRENT_USER()' is expand to the user of slave
SQL thread, but SQL thread's user name always NULL. This breaks the replication.
After this patch, session's user will be written into query log events
if these statements call CURREN_USER() or 'ALTER EVENT' does not assign a definer.
Apart strict-aliasing warnings, fix the remaining warnings
generated by GCC 4.4.4 -Wall and -Wextra flags.
One major source of warnings was the in-house function my_bcmp
which (unconventionally) took pointers to unsigned characters
as the byte sequences to be compared. Since my_bcmp and bcmp
are deprecated functions whose only difference with memcmp is
the return value, every use of the function is replaced with
memcmp as the special return value wasn't actually being used
by any caller.
There were also various other warnings, mostly due to type
mismatches, missing return values, missing prototypes, dead
code (unreachable) and ignored return values.
MERGE engine".
Backport the patch from 6.0 by Ingo Struewing:
revid:ingo.struewing@sun.com-20091028183659-6kmv1k3gdq6cpg4d
Bug#36171 - CREATE TEMPORARY TABLE and MERGE engine
In former MySQL versions, up to 5.1.23/6.0.4 it was possible to create
temporary MERGE tables with non-temporary MyISAM tables.
This has been changed in the mentioned version due to Bug 19627
(temporary merge table locking). MERGE children were locked through
the parent table. If the parent was temporary, it was not locked and
so the children were not locked either. Parallel use of the MyISAM
tables corrupted them.
Since 6.0.6 (WL 4144 - Lock MERGE engine children), the children are
locked independently from the parent. Now it is possible to allow
non-temporary children with a temporary parent. Even though the
temporary MERGE table itself is not locked, each non-temporary
MyISAM table is locked anyway.
NOTE: Behavior change: In 5.1.23/6.0.4 we prohibited non-temporary
children with a temporary MERGE table. Now we re-allow it.
An important side-effect is that temporary tables, which overlay
non-temporary MERGE children, overlay the children in the MERGE table.
and a backport of relevant changes from the 6.0
version of the fix done by Ingo Struewing.
The bug itself was fixed by the patch for Bug#54811.
MyISAMMRG engine would try to use MMAP on its children
even on platforms that don't support it and even if
myisam_use_mmap option was off.
This lead to an infinite hang in INSERT ... SELECT into
a MyISAMMRG table when the destination MyISAM table
was also selected from.
A bug in duplicate detection fixed by 54811 was essential to
the hang - when a duplicate is detected, the optimizer
disables the use of memory mapped files, and it wasn't the case.
The patch below is also to not turn on MMAP on children tables
if myisam_use_mmap is off.
A test case is added to cover MyISAMMRG and myisam_use_mmap
option.
