OLD VALUE OF INPUT PARAMETER.
The user-visible problem was that CASE-control-flow function
(not CASE-statement) misbehaved in stored routines under some
circumstances. The problem resulted in a crash or wrong data
returned. The error happened when expressions in CASE-function
were not of the same character set.
A CASE-function should return values of the same character set
for all branches. Internally, that means a new Item-instance
for the CONVERT(... USING <some charset>)-function is added
to the item tree when needed. The problem was that such changes
were not properly recorded using THD::change_item_tree(),
thus dangling pointers remain in the item tree after
THD::rollback_item_tree_changes(), which lead to undefined
behavior (i.e. crash / wrong data) for subsequent executions of
the stored routine.
This bug was introduced by a patch for Bug 11753363
(44793 - CHARACTER SETS: CASE CLAUSE, UCS2 OR UTF32, FAILURE).
The fixed function is Item_func_case::fix_length_and_dec().
New CONVERT-items are added in agg_item_set_converter(),
which calls THD::change_item_tree().
The problem was that an intermediate array was passed
to agg_item_set_converter(). Thus, THD::change_item_tree() there
was called on intermediate objects.
Note: those intermediate objects are allocated on THD's
memory root, so it's Ok to put them into "changed item lists".
The fix is to track changes on the correct objects.
The check for empty password in the user account was checking the wrong field.
Fixed to check the proper password hash.
Test case added.
Fixed native_password and old_password plugins that suffered from the same
problems.
Unambuguated the auth_string ACL_USER member : previously it was used for
both password and the authentication string (depending on the plugin). Now
fixed to contain either the authentication string specified or empty string.
SECONDARY INDEX IN INNODB
This is a follow-up patch.
This patch moves part of the new test coverage to a test
file that is only run on debug builds since it used debug-
only features and therefore broke the test case on
release builds.
SECONDARY INDEX IN INNODB
The patches for Bug#11751388 and Bug#11784056 enabled concurrent
reads while creating secondary indexes in InnoDB. However, they
introduced a regression. This regression occured if ALTER TABLE
failed after the index had been added, for example during the
lock upgrade needed to update .FRM. If this happened, InnoDB
and the server got out of sync with regards to which indexes
actually existed. Therefore the patch for Bug#11815600 again
disabled concurrent reads.
This patch re-enables concurrent reads. The original regression
is fixed by splitting the ADD INDEX operation into two parts.
First the new index is created but not made active. This is
done while concurrent reads are allowed. The second part of
the operation makes the index active (or reverts the change).
This is done after lock upgrade, which prevents the original
regression.
In order to implement this change, the patch changes the storage
API for in-place index creation. handler::add_index() is split
into two functions, handler_add_index() and
handler::final_add_index(). The former for creating indexes without
making them visible and the latter for commiting (i.e. making
visible) new indexes or reverting the changes.
Large parts of this patch were written by Marko Mäkelä.
Test case added to innodb_mysql_lock.test.
The test case problem stemmed from the fact that a debug sync
signal is a global variable that persists until overwritten
by a new signal. This means that if two different signals
are raised in sequence, a thread waiting for the first signal
might miss it if the second signal sets the global variable
before the thread wakes up.
The solution is to deliver a subsequent signal only after the
waiting thread has received it.
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.
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.
LEAK WITH PARTITIONED ARCHIVE TABLES
CHECK TABLE against archive table, when file descriptors
are exhausted, caused server crash.
Archive didn't handle errors when opening data file for
CHECK TABLE.
There are two problems:
1. There is a missing check for 'year' parameter(year can not be greater than 9999) in
makedate function. fix: added check that year can not be greater than 9999.
2. There is a missing check for zero date in from_days() function.
fix: added zero date check into Item_func_from_days::get_date()
function.
Impementing Test Review Comment.
Bug test scenario:
SELECT is not returning result set for "equal" (=) and "NULL safe equal
operator" (<=>) on BIT data type. Extending this scenario for all data types
and innodb
The 5.5 version of the patch.
The server doesn't restrict the data that can be inserted into integer columns
with explicitly specified length that's smaller than what the type can handle,
e.g. 1234 can be inserted into an INT(2) column just fine.
Thus, when calcualting the maximum width of expressions involving such
restricted integer columns we need to use the implicit maximum width of
the field instead of the explicitly speficied one.
Fixed the server to use the implicit maximum in such cases and made sure
the implicit maximum is addjusted the same way as the explicit one wrt
signedness.
Fixed several test case results (ctype_*.result, metadata.result and
type_ranges.result) to reflect the extended column widths.
Added a regression test case in distinct.test.
Note : this is the behavior preserving fix that makes 5.5 behave as 5.1 and
earlier. In the mysql trunk we'll add a insert time check for the explict
maximum size.
Attempts to assign value to a table column from trigger by using
NEW.column_name pseudo-variable might result in garbled data.
That happened when:
- the column had a BLOB-based type (e.g. TEXT)
and
- the value being assigned was retrieved from stored routine variable
of the same type.
The problem was that BLOB values were not copied correctly in this
case. Instead of doing a copy of a real value, the value's representation
in record buffer was copied. This representation is essentially a
pointer to a buffer associated with the virtual table for routine
variables where the real value is stored. Since this buffer got
freed once trigger was left or could have changed its contents when
new value was assigned to corresponding routine variable such a shallow
copying resulted in garbled data in NEW.colum_name column.
It worked in 5.1 due to a subtle bug in create_virtual_tmp_table():
- in 5.1 create_virtual_tmp_table() returned a table which
had db_low_byte_first == false.
- in 5.5 and up create_virtual_tmp_table() returns a table which
has db_low_byte_first == true.
Actually, db_low_byte_first == false only for ISAM storage engine,
which was deprecated and removed in 5.0.
Having db_low_byte_first == false led to getting false in the
complex condition for the 2nd "if" in field_conv(), which in turn
led to copy-blob-behavior as a fall-back strategy:
- to->table->s->db_low_byte_first was true (correct value)
- from->table->s->db_low_byte_first was false (incorrect value)
In 5.5 and up that condition is true, which means blob-values are
not copied.
WORK WITH --START-POSITION
If setting --start-position to start after the FD event, mysqlbinlog
will output an error stating that it has not found an FD event.
However, its not that mysqlbinlog does not find it but rather that it
does not processes it in the regular way (i.e., it does not print it).
Given that one is using --base64-output=DECODE-ROWS then not printing
it is actually fine.
To fix this, we make mysqlbinlog not to complain when it has not
printed the FD event, is outputing in base64, but is decoding the
rows.
The problem was that wrong structure of mysql.event was not detected and
the server continued to use wrongly-structured data.
The fix is to check the structure of mysql.event after opening before
any use. That makes operations with events more strict -- some operations
that might work before throw errors now. That seems to be Ok.
Another side-effect of the patch is that if mysql.event is corrupted,
unrelated DROP DATABASE statements issue an SQL warning about inability
to open mysql.event table.
