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.
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.
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
For a join query with GROUP BY and/or ORDER BY and a view reference
in the FROM list the metadata erroneously showed empty table aliases
and database names for the view columns.
Changed code to enforce that SQL_CACHE only in the first SELECT is used to turn on caching(as documented), but any SQL_NO_CACHE will turn off caching (not documented, but a useful behaviour, especially for machine generated queries). Added test cases to explicitly test the documented caching behaviour and test cases for the reported bug.
represented by an expression of the type UNSIGNED INT and this
expression was evaluated to 0 then the function erroneously returned
the value of the first argument instead of an empty string.
This problem was introduced by the patch for bug 10963.
The problem has been resolved by a proper modification of the code of
Item_func_substr::val_str.
