impossible WHERE/HAVING clause
(subselect_single_select_engine::exec).
Allocation and initialization of joined table list t1, t2... of
subqueries like:
NOT IN (SELECT ... FROM t1,t2,... WHERE 0)
is optimized out, however server tries to traverse this list.
Grouping or ordering of long values in not indexed BLOB/TEXT columns
with GBK or BIG5 charsets crashes the server.
MySQL server uses sorting (the filesort procedure) in the temporary
table to evaluate the GROUP BY clause in case of lack of suitable index.
That procedure takes into account only first @max_sort_length bytes
(system variable, usually 1024) of TEXT/BLOB sorting key string.
The my_strnxfrm_gbk and my_strnxfrm_big5 fill temporary keys
with data of whole blob length instead of @max_sort_length bytes
length. That buffer overrun has been fixed.
Make maximum blob size to be 2**32-1, regardless of word size.
Fix failure of timestamp with size of 2**31-1. The method of
rounding up to the nearest even number would overflow.
The problem was that LOAD DATA code (sql_load.cc) didn't take into
account that there may be items, representing references to other
columns. This is a usual case in views. The crash happened because
Item_direct_view_ref was casted to Item_user_var_as_out_param,
which is not a base class.
The fix is to
1) Handle references properly;
2) Ensure that an item is treated as a user variable only when
it is a user variable indeed;
3) Report an error if LOAD DATA is used to load data into
non-updatable column.
Mixing aggregate functions and non-grouping columns is not allowed in the
ONLY_FULL_GROUP_BY mode. However in some cases the error wasn't thrown because
of insufficient check.
In order to check more thoroughly the new algorithm employs a list of outer
fields used in a sum function and a SELECT_LEX::full_group_by_flag.
Each non-outer field checked to find out whether it's aggregated or not and
the current select is marked accordingly.
All outer fields that are used under an aggregate function are added to the
Item_sum::outer_fields list and later checked by the Item_sum::check_sum_func
function.
View definition as SELECT ... FROM DUAL WHERE ... has
valid syntax, but use of such view in SELECT or
SHOW CREATE VIEW syntax causes unexpected syntax error.
Server omits FROM DUAL clause when storing view body
string in a .frm file for further evaluation.
However, syntax of SELECT-witout-FROM query is more
restrictive than SELECT FROM DUAL syntax, and doesn't
allow the WHERE clause.
NOTE: this syntax difference is not documented.
View registration procedure has been modified to
preserve original structure of view's body.
localhost/default port
When creating federated table that points to unspecified host or
localhost on unspecified port or port is 0, small memory leak occurs.
This happens because we make a copy of unix socket path, which is
never freed.
With this fix we do not make a copy of unix socket path, instead
share->socket points to MYSQL_UNIX_ADDR constant directly.
This fix is covered by a test case for BUG34788.
Affects 5.0 only.
correctly - crashes server !
Creating federated table with connect string containing empty
(zero-length) host name and port is evaluated as 0 (port is
incorrect, omitted or 0) crashes server.
This happens because federated calls strcmp() with NULL pointer.
Fixed by avoiding strcmp() call if hostname is set to NULL.
binlogging of insert into a autoincrement blackhole table ignored
an explicit set insert_id.
Fixed with refining of the blackhole's insert method to call
update_auto_increment() that prepares binlogging the insert query
with the preceeding set insert_id.
Note, as the engine does not store any actual data one has to explicitly
provide to the server with the value of the autoincrement column via
set insert_id. Otherwise binlogging will happend with the default
set insert_id=1.
When swapping out heap I_S tables to disk, this is done after plan refinement.
Thus, READ_RECORD::file will still point to the (deleted) heap handler at start
of execution. This causes segmentation fault if join buffering is used and the
query is a star query where the result is found to be empty before accessing
some table. In this case that table has not been initialized (i.e. had its
READ_RECORD re-initialized) before the cleanup routine tries to close the handler.
Fixed by updating READ_RECORD::file when changing handler.
Bug #18453 Warning/error message if there is a mismatch between ...
There were three problems:
1. the reported lack of warnings for the BEFORE syntax of PURGE;
2. the similar lack of warnings for the TO syntax;
3. incompatible behaviour between the two in that the latter blanked out
regardlessly of presence or lack the actual file corresponding to
an index record; the former version gave up at the first mismatch.
fixed with deploying the warning's generation and synronizing logics of
purge_logs() and purge_logs_before_date().
my_stat() is called in either of two branches of purge_logs() (responsible
for the TO syntax of PURGE) similarly to how it has behaved in the BEFORE syntax.
If there is no actual binlog file, my_stat returns NULL and my_delete is
not invoked.
A critical error is reported to the user if a file from the index
could not be retrieved info about or deleted with a system error code
different than ENOENT.
