When a UNION statement forced conversion of an UTF8
charset value to a binary charset value, the byte
length of the result values was truncated to the
CHAR_LENGTH of the original UTF8 value.
spaces.
When the my_strnncollsp_simple function compares two strings and one is a prefix
of another then this function compares characters in the rest of longer key
with the space character to find whether the longer key is greater or less.
But the sort order of the collation isn't used in this comparison. This may
lead to a wrong comparison result, wrongly created index or wrong order of the
result set of a query with the ORDER BY clause.
Now the my_strnncollsp_simple function uses collation sort order to compare
the characters in the rest of longer key with the space character.
query / no aggregate of subquery
The optimizer counts the aggregate functions that
appear as top level expressions (in all_fields) in
the current subquery. Later it makes a list of these
that it uses to actually execute the aggregates in
end_send_group().
That count is used in several places as a flag whether
there are aggregates functions.
While collecting the above info it must not consider
aggregates that are not aggregated in the current
context. It must treat them as normal expressions
instead. Not doing that leads to incorrect data about
the query, e.g. running a query that actually has no
aggregate functions as if it has some (and hence is
expected to return only one row).
Fixed by ignoring the aggregates that are not aggregated
in the current context.
One other smaller omission discovered and fixed in the
process : the place of aggregation was not calculated for
user defined functions. Fixed by calling
Item_sum::init_sum_func_check() and
Item_sum::check_sum_func() as it's done for the rest of
the aggregate functions.
Thanks to Martin Friebe for finding and submitting a fix for this bug!
A table with maximum number of key segments and maximum length key name
would have a corrupted .frm file, due to an incorrect calculation of the
complete key length. Now the key length is computed correctly (I hope) :-)
MyISAM would reject a table with the maximum number of keys and the maximum
number of key segments in all keys. It would allow one less than this total
maximum. Now MyISAM accepts a table defined with the maximum. (This is a
very minor issue.)
Sometimes special 0 ENUM values was ALTERed to normal
empty string ENUM values.
Special 0 ENUM value has the same string representation
as normal ENUM value defined as '' (empty string).
The do_field_string function was used to convert
ENUM data at an ALTER TABLE request, but this
function doesn't care about numerical "indices" of
ENUM values, i.e. do_field_string doesn't distinguish
a special 0 value from an empty string value.
A new copy function called do_field_enum has been added to
copy special 0 ENUM values without conversion to an empty
string.
a lookup into a BINARY index by a key ended with spaces. It caused
an assertion abort for a debug version and wrong results for non-debug
versions.
The problem occurred because the function _mi_pack_key stripped off
the trailing spaces from binary search keys while the function _mi_make_key
did not do it when keys were inserted into the index.
Now the function _mi_pack_key does not remove the trailing spaces from
search keys if they are of the binary type.
LOCK TABLES takes a list of tables to lock. It may lock several
tables successfully and then encounter a tables that it can't lock,
e.g. because it's locked. In such case it needs to undo the locks on
the already locked tables. And it does that. But it has also notified
the relevant table storage engine handlers that they should lock.
The only reliable way to ensure that the table handlers will give up
their locks is to end the transaction. This is what UNLOCK TABLE
does : it ends the transaction if there were locked tables by LOCK
tables.
It is possible to end the transaction when the lock fails in
LOCK TABLES because LOCK TABLES ends the transaction at its start
already.
Fixed by ending (again) the transaction when LOCK TABLES fails to
lock a table.
the loose scan optimization for grouping queries was applied returned
a wrong result set when the query was used with the SQL_BIG_RESULT
option.
The SQL_BIG_RESULT option forces to use sorting algorithm for grouping
queries instead of employing a suitable index. The current loose scan
optimization is applied only for one table queries when the suitable
index is covering. It does not make sense to use sort algorithm in this
case. However the create_sort_index function does not take into account
the possible choice of the loose scan to implement the DISTINCT operator
which makes sorting unnecessary. Moreover the current implementation of
the loose scan for queries with distinct assumes that sorting will
never happen. Thus in this case create_sort_index should not call
the function filesort.
INSERT into table from SELECT from the same table
with ORDER BY and LIMIT was inserting other data
than sole SELECT ... ORDER BY ... LIMIT returns.
One part of the patch for bug #9676 improperly pushed
LIMIT to temporary table in the presence of the ORDER BY
clause.
That part has been removed.
Problem: separator was not converted to the result character set,
so the result was a mixture of two different character sets,
which was especially bad for UCS2.
Fix: convert separator to the result character set.
The reason the "reap;" succeeds unexpectedly is because the query was completing(almost always) and the network buffer was big enough to store the query result (sometimes) on Windows, meaning the response was completely sent before the server thread could be killed.
Therefore we use a much longer running query that doesn't have a chance to fully complete before the reap happens, testing the kill properly.
- When creating an index for the sort, the number of rows plus 1 is used
to allocate a buffer. In this test case, the number of rows 4294967295
is the max value of an unsigned integer, so when 1 was added to it, a
buffer of size 0 was allocated causing the crash.
- Create new test suite for this bug's test suite as per QA.
Occasionally mysqlbinlog --hexdump failed with error:
ERROR 1064 (42000) at line ...: You have an error in your
SQL syntax; check the manual that corresponds to your MySQL
server version for the right syntax to use near
'Query thread_id=... exec_time=... error_code=...
When the length of hexadecimal dump of binlog header was
divisible by 16, commentary sign '#' after header was lost.
The Log_event::print_header function has been modified to always
finish hexadecimal binlog header with "\n# ".
The abort happened when a query contained a conjunctive predicate
of the form 'view column = constant' in the WHERE condition and
the grouping list also contained a reference to a view column yet
a different one.
Removed the failing assertion as invalid in a general case.
Also fixed a bug that prevented applying some optimization for grouping
queries using views. If the WHERE condition of such a query contains
a conjunctive condition of the form 'view column = constant' and
this view column is used in the grouping list then grouping by this
column can be eliminated. The bug blocked performing this elimination.
and replicated):
A DROP USER statement with a non-existing user was correctly written to
the binary log (there might be users that were removed, but not all),
but the error code was not set, which caused the slave to stop with an
error.
The error reporting code was moved to before the statement was logged
to ensure that the error information for the thread was correctly set
up. This works since my_error() will set the fields net.last_errno and
net.last_error for the thread that is reporting the error, and this
will then be picked up when the Query_log_event is created and written
to the binary log.
slave_sql thread calls thd->clear_error() to force error to be ignored,
though this method didn't clear thd->killed state, what causes
slave_sql thread to stop.
clear thd->killed state if we ignore an error
