The problem was due to a prior fix for BUG 9676, which limited
the rows stored in a temporary table to the LIMIT clause. This
optimization is not applicable to non-group queries with aggregate
functions. The fix disables the optimization in this case.
- Fix typo in Item_func_export_set::fix_length_and_dec() which caused character set aggregation to fail
- Remove default argument from last arg of agg_arg_charsets() function, to reduce potential errors
Remove some sql_print_error() calls which were triggered by user error (i.e., not server-level events at all).
Also, convert an sql_print_error -> sql_print_information for a non-error server event.
GROUP BY/DISTINCT pruning optimization must be done before ORDER BY
optimization because ORDER BY may be removed when GROUP BY/DISTINCT
sorts as a side effect, e.g. in
SELECT DISTINCT <non-key-col>,<pk> FROM t1
ORDER BY <non-key-col> DISTINCT
must be removed before ORDER BY as if done the other way around
it will remove both.
The crash was caused by invalid sequence of handler::** calls:
ha_smth->index_init();
ha_smth->index_next_same(); (2)
(2) is an invalid call as it was not preceeded by any 'scan setup' call
like index_first() or index_read(). The cause was that QUICK_SELECT::reset()
didn't "fully reset" the quick select- current QUICK_RANGE wasn't forgotten,
and quick select might attempt to continue reading the range, which would
result in the above mentioned invalid sequence of handler calls.
5.x versions are not affected by the bug - they already have the missing
"range=NULL" clause.
bug #18184 SELECT ... FOR UPDATE does not work..: New test case
ha_ndbcluster.h, ha_ndbcluster.cc, NdbConnection.hpp:
Fix for bug #21059 Server crashes on join query with large dataset with NDB tables: Releasing operation for each intermediate batch, before next call to trans->execute(NoCommit);
- if there are two character set definitions in the column declaration,
we replace the first one with the second one as we store both in the LEX->charset
slot. Add a separate slot to the LEX structure to store underscore charset.
- convert default values to the column charset of STRING, VARSTRING fields
if necessary as well.
Socket timeouts in client library were used only on Windows.
The solution is to use socket timeouts in client library on all
systems were they are supported.
No test case is provided because it is impossible to simulate network
failure in current test suit.
Make the encryption functions MD5(), SHA1() and ENCRYPT() return binary results.
Make MAKE_SET() and EXPORT_SET() use the correct character set for their default separator strings.
didn't work as expected: collation_server was set not to xxx,
but to the default collation of character set "yyy".
With different argument order it worked as expected:
mysqld --character-set-server=yyy --collation-server=yyy
Fix:
initializate default_collation_name to 0
when processing --character-set-server
only if --collation-server has not been specified
in command line.
time_format() claimed %H and %k would return at most two digits
(hours 0-23), but this coincided neither with actual behaviour
nor with docs. this is not visible in simple queries; forcing
a temp-table is probably the easiest way to see this. adjusted
the return-length appropriately; the alternative would be to
adjust the docs to say that behaviour for > 99 hours is undefined.
---
Bug#19844: time_format in Union truncates values
time_format() claimed %H and %k would return at most two digits
(hours 0-23), but this coincided neither with actual behaviour
nor with docs. this is not visible in simple queries; forcing
a temp-table is probably the easiest way to see this. adjusted
the return-length appropriately; the alternative would be to
adjust the docs to say that behaviour for > 99 hours is undefined.
privileges
This problem is 4.1 specific. It doesn't affect 4.0 and was fixed
in 5.x before.
Having any mysql user who is allowed to issue multi table update
statement and any column/table grants, allows this user to update
any table on a server (mysql grant tables are not exception).
check_grant() accepts number of tables (in table list) to be checked
in 5-th param. While checking grants for multi table update, number
of tables must be 1. It must never be 0 (actually we have
DBUG_ASSERT(number > 0) in 5.x in grant_check() function).
When processing aggregate functions all tables values are reset
to NULLs at the end of each group.
When doing that if there are no rows found for a group
the const tables must not be reset as they are not recalculated
by do_select()/sub_select() for each group.
Too many cursors (more than 1024) could lead to memory corruption.
This affects both, stored routines and C API cursors, and the
threshold is per-server, not per-connection. Similarly, the
corruption could happen when the server was under heavy load
(executing more than 1024 simultaneous complex queries), and this is
the reason why this bug is fixed in 4.1, which doesn't support
cursors.
The corruption was caused by a bug in the temporary tables code, when
an attempt to create a table could lead to a write beyond allocated
space. Note, that only internal tables were affected (the tables
created internally by the server to resolve the query), not tables
created with CREATE TEMPORARY TABLE. Another pre-condition for the
bug is TRUE value of --temp-pool startup option, which, however, is a
default.
The cause of a bug was that random memory was overwritten in
bitmap_set_next() due to out-of-bound memory access.
