Problem was block_size on partitioned tables was not set,
resulting in keys_per_block was not correct which affects
the cost calculation for read time of indexes (including
cost for group min/max).Which resulted in a bad optimizer
decision.
Fixed by setting stats.block_size correctly.
mode
When the master was executing in sql_mode='traditional' (which
implies that really_abort_on_warning returns TRUE - because of
MODE_STRICT_ALL_TABLES), the error code (ER_DUP_ENTRY in the
reported case) was not being set in the
Query_log_event. Therefore, even if a failure was to be expected
when replaying the statement on the slave, a failure would occur,
because the Query_log_event was not transporting the expected
error code, but 0 instead.
This was because when the master was getting the error code to
set it in the Query_log_event, the executing thread would be
assumed to have been killed:
THD::killed==THD::KILL_BAD_DATA. This would make the error code
fetch routine not to check thd->main_da.sql_errno(), but instead
the thd->killed value. What's more, is that the server would
thd->killed value if thd->killed == THD::KILL_BAD_DATA and return
0 instead. So this is a double inconsistency, as the we should
not even check thd->killed but rather thd->main_da.sql_errno().
We fix this by extending the condition used to choose whether to
check the thd->main_da.sql_errno() or thd->killed, so that it
takes into consideration the case when:
thd->killed==THD::KILL_BAD_DATA.
+ failing statements
Implicit DROP event for temporary table is not getting
LOG_EVENT_THREAD_SPECIFIC_F flag, because, in the previous
executed statement in the same thread, which might even be a
failed statement, the thread_specific_used flag is set to
FALSE (in mysql_reset_thd_for_next_command) and not set to TRUE
before connection is shutdown. This means that implicit DROP
event will take the FALSE value from thread_specific_used and
will not set LOG_EVENT_THREAD_SPECIFIC_F in the event header. As
a consequence, mysqlbinlog will not print the pseudo_thread_id
from the DROP event, because one of the requirements for the
printout is that this flag is set to TRUE.
We fix this by setting thread_specific_used whenever we are
binlogging a DROP in close_temporary_tables, and resetting it to
its previous value afterward.
If an outer query is broken, a subquery might not even get set up.
EXPLAIN EXTENDED did not expect this and merrily tried to de-ref all
of the half-setup info.
We now catch this case and print as much as we have, as it doesn't cost us
anything (doesn't make regular execution slower).
backport from 5.1
This patch fixes some typos and poorly formulated sentences in
the output from mysqld --help --verbose.
Some of the problems described in the bug report are already
handled by the patch for Bug#49447, and are therefore not
included in this patch.
for same data when using bit fields
Problem: checksum for BIT fields may be computed incorrectly
in some cases due to its storage peculiarity.
Fix: convert a BIT field to a string then calculate its checksum.
A client doing multiple mysql_library_init() and
mysql_library_end() calls over the lifetime of the process may
experience lost character set data, potentially even a
SIGSEGV.
This patch reinstates the reloading of character set data when
a mysql_library_init() is done after a mysql_library_end().
Incremental commit based on previous patch.
Addresses reviewer comments to move reseting of
thd->current_stmt_binlog_row_based to after binlog_query
takes place.
The problem is that cond->fix_fields(thd, 0) breaks
condition(cuts off 'having'). The reason of that is
that NULL valued Item pointer is present in the
middle of Item list and it breaks the Item processing
loop.
performance degradation.
Filesort + join cache combination is preferred to full index scan because it
is usually faster. But it's not the case when the index is clustered one.
Now test_if_skip_sort_order function prefers filesort only if index isn't
clustered.
Propagation of a large unsigned numeric constant
in the WHERE expression led to wrong result.
For example,
"WHERE a = CAST(0xFFFFFFFFFFFFFFFF AS USIGNED) AND FOO(a)",
where a is an UNSIGNED BIGINT, and FOO() accepts strings,
was transformed to "... AND FOO('-1')".
That has been fixed.
Also EXPLAIN EXTENDED printed incorrect numeric constants in
transformed WHERE expressions like above. That has been
fixed too.
The problem was in an incorrect debug assertion. The expression
used in the failing assertion states that when finding
references matching ORDER BY expressions, there can be only one
reference to a single table. But that does not make any sense,
all test cases for this bug are valid examples with multiple
identical WHERE expressions referencing the same table which
are also present in the ORDER BY list.
Fixed by removing the failing assertion. We also have to take
care of the 'found' counter so that we count multiple
references only once. We rely on this fact later in
eq_ref_table().
For temporary tables that are created with an engine that does
not provide the HTON_CAN_RECREATE, the truncate operation is
performed resorting to the optimized handler::ha_delete_all_rows
method. However, this means that the truncate will share
execution path, from mysql_delete, with truncate on regular
tables and other delete operations. As a consequence the truncate
operation, for the temporary table is logged, even if in row mode
because there is no distinction between this and the other delete
operations at binlogging time.
We fix this by checking if: (i) the binlog format, when the
truncate operation was issued, is ROW; (ii) if the operation is a
truncate; and (iii) if the table is a temporary table; before
writing to the binary log. If all three conditions are met, we
skip writing to the binlog. A side effect of this fix is that we
limit the scope of setting and resetting the
current_stmt_binlog_row_based. Now we just set and reset it
inside mysql_delete in the boundaries of the
handler::ha_write_row loop. This way we have access to
thd->current_stmt_binlog_row_based real value inside
mysql_delete.
"TYPE=storage_engine" is deprecated, and will be removed
in the Celosia release of MySQL. Since the option is
present in the Betony release and the version number of
Celosia is still not decided, we need to bump the
deprecation version number back up to "6.0".
When EXPLAIN EXTENDED tries to print column names, it checks whether the
referenced table is CONST (in which case, the column's value rather than
its name will be printed). If no proper table is reference (i.e. because
a derived table was used that has since gone out of scope), this will fail
spectacularly.
This ports an equivalent of the fix for Bug 43354.
CHECK_FIELD_IGNORE was treated as CHECK_FIELD_ERROR_FOR_NULL;
UPDATE...SET...NULL on NOT NULL fields behaved differently after
a trigger.
Now distinguishes between IGNORE and ERROR_FOR_NULL and save/restores
check-field options.
I found three issues during the analysis:
1. Memory leak caused by temp_buf not being freed;
2. Memory leak caused when handling argv;
3. Conditional jump that depended on unitialized values.
Issue #1
--------
DESCRIPTION: when mysqlbinlog is reading from a remote location
the event temp_buf references the incoming stream (in NET
object), which is not freed by mysqlbinlog explicitly. On the
other hand, when it is reading local binary log, it points to a
temporary buffer that needs to be explicitly freed. For both
cases, the temp_buf was not freed by mysqlbinlog, instead was
set to 0. This clearly disregards the free required in the
second case, thence creating a memory leak.
FIX: we make temp_buf to be conditionally freed depending on
the value of remote_opt. Found out that similar fix is already
in most recent codebases.
Issue #2
--------
DESCRIPTION: load_defaults is called by parse_args, and it
reads default options from configuration files and put them
BEFORE the arguments that are already in argc and argv. This is
done resorting to MEM_ROOT. However, parse_args calls
handle_options immediately after which changes argv. Later when
freeing the defaults, pointers to MEM_ROOT won't match, causing
the memory not to be freed:
void free_defaults(char **argv)
{
MEM_ROOT ptr
memcpy_fixed((char*) &ptr,(char *) argv - sizeof(ptr), sizeof(ptr));
free_root(&ptr,MYF(0));
}
FIX: we remove load_defaults from parse_args and call it
before. Then we save argv with defaults in defaults_argv BEFORE
calling parse_args (which inside can then call handle_options
at will). Actually, found out that this is in fact kind of a
backport for BUG#38468 into 5.1, so I merged in the test case
as well and added error check for load_defaults call.
Fix based on:
revid:zhenxing.he@sun.com-20091002081840-uv26f0flw4uvo33y
Issue #3
--------
DESCRIPTION: the structure st_print_event_info constructor
would not initialize the sql_mode member, although it did for
sql_mode_inited (set to false). This would later raise the
warning in valgrind when printing the sql_mode in the event
header, as this print out is protected by a check against
sql_mode_inited and sql_mode variables. Given that sql_mode was
not initialized valgrind would output the warning.
FIX: we add initialization of sql_mode to the
st_print_event_info constructor.
Table corruption happens during table reading in ha_tina::find_current_row() func.
Field::store() method returns error(true) if stored value is 0.
The fix:
added special case for enum type which correctly processes 0 value.
Additional fix:
INSERT...(default) and INSERT...() have the same behaviour now for enum type.
The problem is that during temporary table creation uneven bits
are not taken into account for hidden fields. It leads to incorrect
calculation&allocation of null bytes size for table record. And
if grouped value is null we set wrong bit for this value(see end_update()).
Fixed by adding separate calculation of uneven bit for hidden fields.
This bug is just one facet of stored routines not being able to
detect changes in meta-data (WL#4179). This particular problem
can be triggered within a single session due to the improper
management of the pre-locking list if the view is expanded after
the pre-locking list is calculated.
Since the overall solution for the meta-data detection issue is
planned for a later release, for now a workaround is used to
fix this particular aspect that only involves a single session.
The workaround is to flush the thread-local stored routine cache
every time a view is created or modified, causing locally cached
routines to be re-evaluated upon invocation.
The problem becomes apparent only if HAVE_purify is undefined.
It related to the part of code placed in open_table_from_share() fuction
where we initialize record buffer only if HAVE_purify is enabled.
So in case of HAVE_purify=OFF record buffer is not initialized
on open table stage.
Next we read key, find NULL value and update appropriate null bit
but do not update record buffer. After that the record is stored
in the join cache(store_record_in_cache). For CHAR fields we
strip trailing spaces and in our case this procedure uses
uninitialized record buffer.
The fix is to skip stripping space procedure in case of null values
for CHAR fields(partially based on 6.0 JOIN_CACHE implementation).
removed in MySQL 6.0
CREATE TABLE... TYPE= returns the warning "The syntax
'TYPE=storage_engine' is deprecated and will be removed in
MySQL 6.0. Please use 'ENGINE=storage_engine' instead"
This syntax is deprecated already from version 5.4.4, so
the message has been changed.
In addition, the deprecation macro was changed to reflect
the ServerPT decision not to include version number in the
warning message.
A number of test result files have been changed as a
consequence of the change in the deprecation macro.
