CRASHES SERVER
Flushing of MERGE table or one of its child tables, which was
locked by flushing thread using LOCK TABLES, might have caused
crashes or assertion failures if the thread failed to reopen
child or parent table.
Particularly, this might have happened when another connection
killed this FLUSH TABLE statement/connection.
Also this problem might have occurred when we failed to reopen
MERGE table or one of its children when executing DDL statement
under LOCK TABLES.
The problem was caused by the fact that reopen_tables() might
have failed to reopen child table but still tried to reopen,
reattach children for and re-lock its parent. Vice versa it
might have failed to reopen parent but kept references from
children to parent around. Since reopen_tables() closes table
it has failed to reopen and therefore frees all associated
memory such dangling references led to crashes when followed.
This patch solves this problem by ensuring that we always close
parent table and all its children if we fail to reopen this
table or one of its children. Same happens if we fail to reattach
children to parent.
Affects 5.1 only.
for compressed InnoDB tables
ha_innodb::info_low(): For calculating data_length or index_length,
use the compressed page size for compressed tables instead of UNIV_PAGE_SIZE.
rb:714 approved by Sunny Bains
There is an optimization of DISTINCT in JOIN::optimize()
which depends on THD::used_tables value. Each SELECT statement
inside SP resets used_tables value(see mysql_select()) and it
leads to wrong result. The fix is to replace THD::used_tables
with LEX::used_tables.
The problem is that TIME_FUZZY_DATE is explicitly used for get_arg0_date()
function in Item_date_typecast::get_date method. The fix is to use real
fuzzy_date value.
The server crashes if it processes table map events that are
corrupted, especially if they map different tables to the same
identifier. This could happen, for instance, due to BUG 56226.
We fix this by checking whether the table map has already been
mapped before actually applying the event. If it has been mapped
with different settings an error is raised and the slave SQL
thread stops. If it has been mapped with same settings the event
is skipped. If the table is set to be ignored by the filtering
rules, there is no change in behavior: the event is skipped and
ids are not checked.
When CREATE TABLE wasn't given ENGINE=... it would determine
the default ENGINE at parse-time rather than at execution
time, leading to incorrect behaviour (namely, later changes
to the default engine being ignore) when calling CREATE TABLE
from a stored procedure.
We now defer working out the default engine till execution of
CREATE TABLE.
We must allocate a larger ref_pointer_array. We failed to account for extra
items allocated here:
#0 find_order_in_list
uint el= all_fields.elements;
all_fields.push_front(order_item); /* Add new field to field list. */
ref_pointer_array[el]= order_item;
order->item= ref_pointer_array + el;
#1 setup_order
#2 setup_without_group
#3 JOIN::prepare
bug. It added this assert;
ut_ad(ind_field->prefix_len);
before a section of code that assumes there is a prefix_len.
The patch replaced code that explicitly avoided this with a check for
prefix_len. It turns out that the purge thread can get to that assert
without a prefix_len because it does not use a row_ext_t* .
When UNIV_DEBUG is not defined, the affect of this is that the purge thread
sets the dfield->len to zero and then cannot find the entry in the index to
purge. So secondary index entries remain unpurged.
This patch does not do the assert. Instead, it uses
'if (ind_field->prefix_len) {...}'
around the section of code that assumes a prefix_len. This is the way the
patch I provided to Marko did it.
The test case is simply modified to do a sleep(10) in order to give the
purge thread a chance to run. Without the code change to row0row.c, this
modified testcase will assert if InnoDB was compiled with UNIV_DEBUG.
I tried to sleep(5), but it did not always assert.
SYNTAX TRIGGERS IN ANY WAY
Table with triggers which were using deprecated (5.0-only) syntax became
unavailable for any DML and DDL after upgrade to 5.1 version of server.
Attempt to execute any statement on such a table resulted in parsing
error reported. Since this included DROP TRIGGER and DROP TABLE
statements (actually, the latter was allowed but was not functioning
properly for such tables) it was impossible to fix the problem without
manual operations on .TRG and .TRN files in data directory.
The problem was that failure to parse trigger body (due to 5.0-only
syntax) when opening trigger file for a table prevented the table
from being open. This made all operations on the table impossible
(except DROP TABLE which due to peculiarity in its implementation
dropped the table but left trigger files around).
This patch solves this problem by silencing error which occurs when
we parse trigger body during table open. Error message is preserved
for the future use and table is marked as having a broken trigger.
We also try to analyze parse tree to recover trigger name, which
will be needed in order to drop the broken trigger. DML statements
which invoke triggers on the table marked as having broken trigger
are prohibited and emit saved error message. The same happens for
DDL which change triggers except DROP TRIGGER and DROP TABLE which
try their best to do what was requested. Table becomes no longer
marked as having broken trigger when last such trigger is dropped.
THE EVENT STATUS.
Any ALTER EVENT statement on a disabled event enabled it back
(unless this ALTER EVENT statement explicitly disabled the event).
The problem was that during processing of an ALTER EVENT statement
value of status field was overwritten unconditionally even if new
value was not specified explicitly. As a consequence this field
was set to default value for status which corresponds to ENABLE.
The solution is to check if status field was explicitly specified in
ALTER EVENT statement before assigning new value to status field.
SEEMS TO BE 'LEAKING' INTO THE SCHEMA NAME SPACE)
and bug#12428824 (Parser stack overflow and crash in sp_add_used_routine
with obscure query).
The first problem was that attempts to call a stored function by
its fully qualified name ended up with unwarranted error "ERROR 1305
(42000): FUNCTION someMixedCaseDb.my_function_name does not exist"
if this function belonged to a schema that had uppercase letters in
its name AND --lower_case_table_names was equal to either 1 or 2.
The second problem was that 5.5 version of MySQL server might have
crashed when a user tried to call stored function with too long name
or too long database name (i.e if a function and database name combined
occupied more than 2*3*64 bytes in utf8). This issue didn't affect
versions of server < 5.5.
The first problem was caused by the fact that in cases when a stored
function was called by its fully qualified name we didn't lowercase
name of its schema before performing look up of the function in
mysql.proc table even although lower_case_table_names mode was on.
As result we were unable to find this function since during its
creation we store lowercased version of schema name in the system
table in this mode and field for schema name uses binary collation.
Calls to stored functions were unaffected by this problem since for
them schema name is converted to lowercase as necessary.
The reason for the second bug was that MySQL Server didn't check length
of function name and database name before proceeding with execution of
stored function. As a consequence too long database name or function
name caused buffer overruns in places where the code assumes that their
length is within fixed limits, like mdl_key_init() in 5.5.
Again this issue didn't affect calls to stored procedures as for them
length of schema name and procedure name are properly checked.
This patch fixes both these bugs by adding calls to check_db_name()
and check_routine_name() to grammar rule which corresponds to a call
to a stored function. These functions ensure that length of database
name and function name for routine called is within standard limit.
Moreover call to check_db_name() handles conversion of database name
to lowercase if --lower_case_table_names mode is on.
Note that even although the second issue seems to be only reproducible
in 5.5 we still add code fixing it to 5.1 to be on the safe side (and
make code a bit more robust against possible future changes).
Problem: in case of wrong data insert into indexed GEOMETRY fields
(e.g. NULL value for a not NULL field) MyISAM reported
"ERROR 126 (HY000): Incorrect key file for table; try to repair it"
due to misuse of the key deletion function.
Fix: always use R-tree key functions for R-tree based indexes
and B-tree key functions for B-tree based indexes.
row_build_index_entry(): In innodb_file_format=Barracuda
(ROW_FORMAT=DYNAMIC or ROW_FORMAT=COMPRESSED), a secondary index on a
full column can refer to a field that is stored off-page in the
clustered index record. Take that into account.
rb:692 approved by Jimmy Yang
BOGUS "THE TABLE MYSQL.PROC IS MISSING,..."
There was a race condition between loading a stored routine
(function/procedure/trigger) specified by fully qualified name
SCHEMA_NAME.PROC_NAME and dropping the stored routine database.
The problem was that there is a window for race condition when one server
thread tries to load a stored routine being executed and the other thread
tries to drop the stored routine schema.
This condition race window exists in implementation of function
mysql_change_db() called by db_load_routine() during loading of stored
routine to cache. Function mysql_change_db() calls check_db_dir_existence()
that might failed because specified database was dropped during concurrent
execution of DROP SCHEMA statement. db_load_routine() calls mysql_change_db()
with flag 'force_switch' set to 'true' value so when referenced db is not found
then my_error() is not called and function mysql_change_db() returns ok.
This shadows information about schema opening error in db_load_routine().
Then db_load_routine() makes attempt to parse stored routine that is failed.
This makes to return error to sp_cache_routines_and_add_tables_aux() but since
during error generation a call to my_error wasn't made and hence
THD::main_da wasn't set we set the generic "mysql.proc table corrupt" error
when running sp_cache_routines_and_add_tables_aux().
The fix is to install an error handler inside db_load_routine() for
the mysql_op_change_db() call, and check later if the ER_BAD_DB_ERROR
was caught.
TO POSITION FIRST CAN CAUSE DATA TO BE CORRUPTED".
ALTER TABLE MODIFY/CHANGE ... FIRST did nothing except renaming
columns if new version of the table had exactly the same
structure as the old one (i.e. as result of such statement, names
of columns changed their order as specified but data in columns
didn't). The same thing happened for ALTER TABLE DROP COLUMN/ADD
COLUMN statements which were supposed to produce new version of
table with exactly the same structure as the old version of table.
I.e. in the latter case the result was the same as if old column
was renamed instead of being dropped and new column with default
as value being created.
Both these problems were caused by the fact that ALTER TABLE
implementation incorrectly interpreted both these situations as
simple renaming of columns and assumed that in-place ALTER TABLE
algorithm could have been used for them.
This patch fixes this problem by ensuring that in cases when some
column is moved to the first position or some column is dropped
the default ALTER TABLE algorithm involving table copying is
always used. This is achieved by detecting such situations in
mysql_prepare_alter_table() and setting Alter_info::change_level
to ALTER_TABLE_DATA_CHANGED for them.
FAIL IN EMBEDDED SERVER
FreeBSD 64 bit needs the FP_X_DNML to fpsetmask() to prevent exceptions from
propagating into mysql (as a threaded application).
However fpsetmask() itself is deprecated in favor of fedisableexcept().
1. Fixed the #ifdef to check for FP_X_DNML instead of i386.
2. Added a configure.in check for fedisableexcept() and, if present,
this function is called insted of the fpsetmask().
No need for new tests, as the existing tests cover this already.
Removed the affected tests from the experimental list.
will create multiple running events.
A CREATE IF NOT EXIST on an event that existed and was enabled caused
multiple instances of the event to run. Disabling the event didn't help.
If the event was dropped, the event stopped running, but when created
again, multiple instances of the event were still running. The only way
to get out of this situation was to restart the server.
The problem was that Event_db_repository::create_event() didn't return
enough information to discriminate between situation when event didn't
exist and was created and when event did exist and was not created
(but a warning was emitted). As result in the latter case event
was added to in-memory queue of events second time. And this led to
unwarranted multiple executions of the same event.
The solution is to add out-parameter to Event_db_repository::create_event()
method which will signal that event was not created because it already
exists and so it should not be added to the in-memory queue.
HA_INNOBASE::UPDATE_ROW, TEMPORARY TABLE, TABLE LOCK".
Attempt to update an InnoDB temporary table under LOCK TABLES
led to assertion failure in both debug and production builds
if this temporary table was explicitly locked for READ. The
same scenario works fine for MyISAM temporary tables.
The assertion failure was caused by discrepancy between lock
that was requested on the rows of temporary table at LOCK TABLES
time and by update operation. Since SQL-layer requested a
read-lock at LOCK TABLES time InnoDB engine assumed that upcoming
statements which are going to be executed under LOCK TABLES will
only read table and therefore should acquire only S-lock.
An update operation broken this assumption by requesting X-lock.
Possible approaches to fixing this problem are:
1) Skip locking of temporary tables as locking doesn't make any
sense for connection-local objects.
2) Prohibit changing of temporary table locked by LOCK TABLES ...
READ.
Unfortunately both of these approaches have drawbacks which make
them unviable for stable versions of server.
So this patch takes another approach and changes code in such way
that LOCK TABLES for a temporary table will always request write
lock. In 5.1 version of this patch switch from read lock to write
lock is done inside of InnoDBs handler methods as doing it on
SQL-layer causes compatibility troubles with FLUSH TABLES WITH
READ LOCK.
Problem: MYSQL_BIN_LOG::reset_logs acquires mutexes in wrong order.
The correct order is first LOCK_thread_count and then LOCK_log. This function
does it the other way around. This leads to deadlock when run in parallel
with a thread that takes the two locks in correct order. For example, a thread
that disconnects will take the locks in the correct order.
Fix: change order of the locks in MYSQL_BIN_LOG::reset_logs:
first LOCK_thread_count and then LOCK_log.
Assertion happens due to missing NULL value check in
Item_func_round::fix_length_and_dec() function.
The fix: added NULL value check for second parameter.
