Original commentary:
Bug #37348: Crash in or immediately after JOIN::make_sum_func_list
The optimizer pulls up aggregate functions which should be aggregated in
an outer select. At some point it may substitute such a function for a field
in the temporary table. The setup_copy_fields function doesn't take this
into account and may overrun the copy_field buffer.
Fixed by filtering out the fields referenced through the specialized
reference for aggregates (Item_aggregate_ref).
Added an assertion to make sure bugs that cause similar discrepancy
don't go undetected.
updates
Attempt to execute trigger or stored function with multi-UPDATE
which used - but didn't update - a table that was also used by
the calling statement led to an error. Read-only reference to
tables used in the calling statement should be allowed.
This problem was caused by the fact that check for conflicting
use of tables in SP/triggers was performed in open_tables(),
and in case of multi-UPDATE we didn't know exact lock type at
this stage.
We solve the problem by moving this check to lock_tables(), so
it can be performed after exact lock types for tables used by
multi-UPDATE are determined.
UNION could convert fixed-point FLOAT(M,D)/DOUBLE(M,D) columns
to FLOAT/DOUBLE when aggregating data types from the SELECT
substatements. While there is nothing particularly wrong with
this behavior, especially when M is greater than the hardware
precision limits, it could be confusing in cases when all
SELECT statements in a union have the same
FLOAT(M,D)/DOUBLE(M,D) columns with equal precision
specifications listed in the same position.
Since the manual is quite vague on what data type should be
returned in such cases, the bug was fixed by implementing the
most 'expected' behavior: do not convert FLOAT(M,D)/DOUBLE(M,D)
to anything else if all SELECT statements in a UNION have the
same precision for that column.
The problem is that the read and write methods of the shared
memory transport (protocol) didn't react to asynchronous close
events, which could lead to a lock up as the client would wait
(until time out) for a server response that will never come.
The solution is to also wait for close events while waiting
for I/O from or to the server.
including modifications according to code review
+ backport of the fix for
Bug 41932 funcs_1: is_collation_character_set_applicability path
too long for tar
which was missing in 5.0 (just a renaming of two files)
When add an aliase name after NAME_CONST, the aliase name will be overwrite.
NAME_CONST will re-set the field's name only if there isn't an aliase in the
function fix-fields().
If there is an aliase, NAME_CONST doesn't re-set the field's name and keeps the old
name.
due to name_const substitution
Problem:
"In general, statements executed within a stored procedure
are written to the binary log using the same rules that
would apply were the statements to be executed in standalone
fashion. Some special care is taken when logging procedure
statements because statement execution within procedures
is not quite the same as in non-procedure context".
For example, each reference to a local variable in SP's
statements is replaced by NAME_CONST(var_name, var_value).
Queries like
"CREATE TABLE ... SELECT FUNC(local_var ..."
are logged as
"CREATE TABLE ... SELECT FUNC(NAME_CONST("local_var", var_value) ..."
that leads to differrent field names and
might result in "Incorrect column name" if var_value is long enough.
Fix: in 5.x we'll issue a warning in such a case.
In 6.0 we should get rid of NAME_CONST().
Note: this issue and change should be described in the documentation
("Binary Logging of Stored Programs").
Fine-tuning. Broke out comparison into method by
suggestion of Davi. Clarified comments. Reverting
test-case which I find too brittle; proper test
case in 5.1+.
(Pushing for Azundris)
We allow security-contexts with NULL users (for
system-threads and for unauthenticated users).
If a non-SUPER-user tried to KILL such a thread,
we tried to compare the user-fields to see whether
they owned that thread. Comparing against NULL was
not a good idea.
If KILLer does not have SUPER-privilege, we
specifically check whether both KILLer and KILLee
have a non-NULL user before testing for string-
equality. If either is NULL, we reject the KILL.
After the table is compressed by the myisampack utility,
opening the table by the server produces valgrind warnings.
This happens because when we try to read a record into the buffer
we alway assume that the remaining buffer to read is always equal
to word size(4 or 8 or 2 bytes) we read. Sometimes we have
remaining buffer size less than word size and trying to read the
entire word size will end up in valgrind errors.
Fixed by reading byte by byte when we detect the remaining buffer
size is less than the word size.
expired timeout on debx86-b in PB
Moved the resource-intensive test case for bug #41486 into
a separate test file to reduce execution time for mysql.test.
When do 'insert delayed' operation, the time_zone info doesn't be keeped in the row info.
So when we do insert sometime later, time_zone didn't write into binlog.
This will cause wrong result for timestamp column in slave.
Our solution is that adding time_zone info with the delayed-row and
restoring time_zone from row-info when execute that row in the furture by another thread.
So we can write correct time_zone info into binlog and got correct result in slave.
Details for Bug#43015 main.lock_multi: Weak code (sleeps etc.)
-------------------------------------------------------------
- The fix for bug 42003 already removed a lot of the weaknesses mentioned.
- Tests showed that there are unfortunately no improvements of this tests
in MySQL 5.1 which could be ported back to 5.0.
- Remove a superfluous "--sleep 1" around line 195
Details for Bug#43065 main.lock_multi: This test is too big if the disk is slow
-------------------------------------------------------------------------------
- move the subtests for the bugs 38499 and 36691 into separate scripts
- runtime under excessive parallel I/O load after applying the fix
lock_multi [ pass ] 22887
lock_multi_bug38499 [ pass ] 536926
lock_multi_bug38691 [ pass ] 258498
Don't throw an error after checking the first and the second arguments.
Continue with checking the third and higher arguments and if some of
them is stronger according to coercibility rules,
then this argument's collation is set as result collation.
When loading dump created by mysqldump tool an error is
thrown saying storage engine for the table doesn't have
an option.
mysqldump tries to re-insert the data into the federated
table which causes the error. Since the data is already
available on the remote server, mysqldump shouldn't try
to dump the data again for FEDERATED tables.
As stated in the bug page, it can be considered similar
to the MERGE ENGINE with "view only" nature.
Fixed by adding the "FEDERATED ENGINE" to the exception
list to ignore the data.
~40Mb after mysqldump/import
When the input string exceeds the maximum allowed size for the
internal buffer, batch_readline() returns a truncated string.
Since there was no way for a caller to determine whether the
string was truncated or not, the command line client assumed
batch_readline() to always return the whole input string and
appended a newline character. This resulted in garbled data
when importing dumps containing strings longer than the
maximum input buffer size.
Fixed by adding a flag to the batch_readline() interface to
signal a truncated string to the caller.
Other minor problems fixed during patch implementation:
- The maximum allowed buffer size for batch_readline() was set
up depending on the client's max_allowed_packet value. It does
not actully make any sense, as those variables are not
related. The input buffer size limit is now always set to 1
MB.
- fill_buffer() did not always set the EOF flag.
- The input buffer could actually grow twice as the specified
limit due to insufficient checks in intern_read_line().
Revised patch incorporating cleaner test code brought up during review.
Removed the use of grep and accomplished same actions via SQL / use of the server.
Runs as before on *nix systems and now runs on Windows without Cygwin as well.
Since there is more than one duplicate value in the table, when adding the
unique index it is not deterministic which value will be reported as causing a
problem. Replace the reported value with '' so that it doesn't affect the
results.
--ignore-table option
mysqldump would correctly omit temporary tables for views, but would
incorrectly still emit all CREATE VIEW statements.
Backport a fix from 5.1, where we capture the names we want to emit
views for in one pass (the placeholder tables) and in the pass where
we actually emit the views, we don't emit a view if it wasn't in that
list.
The copy of the original arguments of a aggregate function was not
initialized until after fix_fields().
Sometimes (e.g. when there's an error processing the statement)
the print() can be called with no corresponding fix_fields() call.
Fixed by adding a check if the Item is fixed before using the arguments
copy.
+ Fix for Bug#43114 wait_until_count_sessions too restrictive, random PB failures
+ Removal of a lot of other weaknesses found
+ modifications according to review
