The GROUP_CONCAT uses its own temporary table. When ROLLUP is present
it creates the second copy of Item_func_group_concat. This copy receives the
same list of arguments that original group_concat does. When the copy is
set up the result_fields of functions from the argument list are reset to the
temporary table of this copy.
As a result of this action data from functions flow directly to the ROLLUP copy
and the original group_concat functions shows wrong result.
Since queries with COUNT(DISTINCT ...) use temporary tables to store
the results the COUNT function they are also affected by this bug.
The idea of the fix is to copy content of the result_field for the function
under GROUP_CONCAT/COUNT from the first temporary table to the second one,
rather than setting result_field to point to the second temporary table.
To achieve this goal force_copy_fields flag is added to Item_func_group_concat
and Item_sum_count_distinct classes. This flag is initialized to 0 and set to 1
into the make_unique() member function of both classes.
To the TMP_TABLE_PARAM structure is modified to include the similar flag as
well.
The create_tmp_table() function passes that flag to create_tmp_field().
When the flag is set the create_tmp_field() function will set result_field
as a source field and will not reset that result field to newly created
field for Item_func_result_field and its descendants. Due to this there
will be created copy func to copy data from old result_field to newly
created field.
Added missing DBUG_xxx_RETURN statements
Fixed some usage of not initialized variables (as found by valgrind)
Ensure that we don't remove locked tables used as name locks from open table cache until unlock_table_names() are called.
This was fixed by having drop_locked_name() returning any table used as a name lock so that we can free it in unlock_table_names()
This will allow Tomas to continue with his work to use namelocks to syncronize things.
Note: valgrind still produces a lot of warnings about using not initialized code and shows memory loss errors when running the ndb tests
¨MySQL server crashes if you try to access to InnoDB table¨
crash caused by schizophrenic mysqld - 2 memory locations for logically same function
with conflicting values.
Fixed by backporting from 5.1 changes to have_xyz_db declarations.
if --skip-grant-tables specified.
The problem is that there is a check that prevents creating a definer
with empty host name.
In --skip-grant-tables mode this check prevents the user from creating a
trigger/view without explicitly specifying its definer. This happens, because
in --skip-grant-tables mode CURRENT_USER is ''@''. According to Sanja this
check was implemented intentionally.
However, according to the MySQL manual it is possible to specify empty host
name (as well as empty user name). Moreover, the behaviour for stored routines
is different in this aspect -- we allow them to be created with implicit
definer.
Based on this, we believe it is OK to change the behaviour for views to be
similar with the behaviour for stored routines.
The idea of the fix is to extend support of non-SUID triggers for backward
compatibility. Formerly non-SUID triggers were appeared when "new" server
is being started against "old" database. Now, they are also created when
"new" slave receives updates from "old" master.
and new binlog format called "mixed" (which is statement-based except if only row-based is correct,
in this cset it means if UDF or UUID is used; more cases could be added in later 5.1 release):
SET GLOBAL|SESSION BINLOG_FORMAT=row|statement|mixed|default;
the global default is statement unless cluster is enabled (then it's row) as in 5.1-alpha.
It's not possible to use SET on this variable if a session is currently in row-based mode and has open temporary tables (because CREATE
TEMPORARY TABLE was not binlogged so temp table is not known on slave), or if NDB is enabled (because
NDB does not support such change on-the-fly, though it will later), of if in a stored function (see below).
The added tests test the possibility or impossibility to SET, their effects, and the mixed mode,
including in prepared statements and in stored procedures and functions.
Caveats:
a) The mixed mode will not work for stored functions: in mixed mode, a stored function will
always be binlogged as one call and in a statement-based way (e.g. INSERT VALUES(myfunc()) or SELECT myfunc()).
b) for the same reason, changing the thread's binlog format inside a stored function is
refused with an error message.
c) the same problems apply to triggers; implementing b) for triggers will be done later (will ask
Dmitri).
Additionally, as the binlog format is now changeable by each user for his session, I remove the implication
which was done at startup, where row-based automatically set log-bin-trust-routine-creators to 1
(not possible anymore as a user can now switch to stmt-based and do nasty things again), and automatically
set --innodb-locks-unsafe-for-binlog to 1 (was anyway theoretically incorrect as it disabled
phantom protection).
Plus fixes for compiler warnings.
- Added empty constructors and virtual destructors to many classes and structs
- Removed some usage of the offsetof() macro to instead use C++ class pointers
Also, moved some of the code out of handler.h and into partition specific files for better
separation.
Also, moved some of the C funcs into partition_info as formal C++ methods
trigger starts trigger".
In short, the deadlock/crash happened when execution of statement, which used
stored functions or activated triggers, coincided with alteration of the
tables used by these functions or triggers (in highly concurrent environment).
Bug was caused by the incorrect handling of tables from prelocked set in
open_tables() functions in situations when refresh happened. This fix replaces
old smart but not very robust way of handling tables after refresh (which was
closing only old tables), with new one which simply closes all tables opened so
far and restarts open_tables().
Also fixed handling of temporary tables in close_tables_for_reopen().
No test case present since bug manifests itself only in concurrent environment.
Before the interval expression was considered to be in seconds, now it is
just a number and the type of interval is considered.
- this changeset introduces also fix for bug#16432 (Events: error re interval
misrepresents the facts)
the code of event_timed::set_interval() was refactored anyway so it is meaningful to
fix the bug in the same changeset.
