* revert part of the db7edfe that moved calculations from
fix_fields to val_str for Item_func_sysconst and descendants
* mark session state dependent functions in check_vcol_func_processor()
* re-run fix_fields for all such functions for every statement
* fix CURRENT_USER/CURRENT_ROLE not to use Name_resolution_context
(that is allocated on the stack in unpack_vcol_info_from_frm())
Note that NOW(), CURDATE(), etc use lazy initialization and do *not*
force fix_fields to be re-run. The rule is:
* lazy initialization is *not* allowed, if it changes metadata (so,
e.g. DAYNAME() cannot use it)
* lazy initialization is *preferrable* if it has side effects (e.g.
NOW() sets thd->time_zone_used=1, so it's better to do it when
the value of NOW is actually needed, not when NOW is simply prepared)
(like DROP TABLE) has been scheduled before conflicting DDL's (like INSERT)
are commited.
What makes these bugs hard to detect is that in most cases any wrong
schduling are caught by MDL locks. It's only when there are timing issues
that the bugs (usually deadlocks) are noticed.
This patch adds a DBUG_ASSERT() that detects, in parallel replication,
if a DDL is scheduled before any depending DML'S are commited.
It does this be checking if there are any conflicting replication locks
when the DDL is about to wait for getting it's MDL lock.
I also did some minor code cleanups in sql_base.cc to make this code
similar to other related code.
.. share->last_version' failed in myisam/mi_open.c:67: test_if_reopen
During the RENAME operation since the renamed temporary table is also
opened and added to myisam_open_list/maria_open_list, resetting the
last_version at the end of operation (HA_EXTRA_PREPARE_FOR_RENAME)
will cause an assertion failure when a subsequent query tries to open
an additional temporary table instance and thus attempts to reuse it
from the open table list.
This commit fixes the issue by skipping flush/close operations executed
toward the end of ALTER for temporary tables. It also enables a shortcut
for simple ALTERs (like rename, disable/enable keys) on temporary
tables.
As safety checks, added some assertions at code points that should not
be hit for temporary tables.
* remove a confusing method name - Field::set_default_expression()
* remove handler::register_columns_for_write()
* rename stuff
* add asserts
* remove unlikely unlikely
* remove redundant if() conditions
* fix mark_unsupported_function() to report the most important violation
* don't scan vfield list for default values (vfields don't have defaults)
* move handling for DROP CONSTRAINT IF EXIST where it belongs
* don't protect engines from Alter_inplace_info::ALTER_ADD_CONSTRAINT
* comments
MDEV-10134 Add full support for DEFAULT
- Added support for using tables with MySQL 5.7 virtual fields,
including MySQL 5.7 syntax
- Better error messages also for old cases
- CREATE ... SELECT now also updates timestamp columns
- Blob can now have default values
- Added new system variable "check_constraint_checks", to turn of
CHECK constraint checking if needed.
- Removed some engine independent tests in suite vcol to only test myisam
- Moved some tests from 'include' to 't'. Should some day be done for all tests.
- FRM version increased to 11 if one uses virtual fields or constraints
- Changed to use a bitmap to check if a field has got a value, instead of
setting HAS_EXPLICIT_VALUE bit in field flags
- Expressions can now be up to 65K in total
- Ensure we are not refering to uninitialized fields when handling virtual fields or defaults
- Changed check_vcol_func_processor() to return a bitmap of used types
- Had to change some functions that calculated cached value in fix_fields to do
this in val() or getdate() instead.
- store_now_in_TIME() now takes a THD argument
- fill_record() now updates default values
- Add a lookahead for NOT NULL, to be able to handle DEFAULT 1+1 NOT NULL
- Automatically generate a name for constraints that doesn't have a name
- Added support for ALTER TABLE DROP CONSTRAINT
- Ensure that partition functions register virtual fields used. This fixes
some bugs when using virtual fields in a partitioning function
Since a query can now refer to the same temporary table
multiple times, find_dup_table()/find_table_in_list()
have been updated to also consider this new possibility.
mysqld maintains a list of TABLE objects for all temporary
tables created within a session in THD. Here each table is
represented by a TABLE object.
A query referencing a particular temporary table for more
than once, however, failed with ER_CANT_REOPEN_TABLE error
because a TABLE_SHARE was allocate together with the TABLE,
so temporary tables always had only one TABLE per TABLE_SHARE.
This patch lift this restriction by separating TABLE and
TABLE_SHARE objects and storing TABLE_SHAREs for temporary
tables in a list in THD, and TABLEs in a list within their
respective TABLE_SHAREs.
- unused TABLE_SHARE::deleting and TABLE_LIST::deleting flags were removed
- kill_delayed_threads_for_table() and intern_close_table() are now private
methods of table cache
- removed free_share flag of closefrm(): it was never used for temporary
tables and was rarely useful for regular tables
- To ensure that mallocs are marked for the correct THD, even if it's
allocated in another thread, I added the thread_id to the THD constructor
- Added st_my_thread_var to thr_lock_info_init() to avoid a call to my_thread_var
- Moved things from THD::THD() to THD::init()
- Moved some things to THD::cleanup()
- Added THD::free_connection() and THD::reset_for_reuse()
- Added THD to CONNECT::create_thd()
- Added THD::thread_dbug_id and st_my_thread_var->dbug_id. These are needed
to ensure that we have a constant thread_id used for debugging with a THD,
even if it changes thread_id (=connection_id)
- Set variables.pseudo_thread_id in constructor. Removed not needed sets.
THAT ACTUALLY EXISTS
ANALYSIS:
=========
Stored functions updating a view where the view table has a
trigger defined that updates another table, fails reporting
an error that the table doesn't exist.
If there is a trigger defined on a table, a variable
'trg_event_map' will be set to a non-zero value after the
parsed tree creation. This indicates what triggers we need to
pre-load for the TABLE_LIST when opening an associated table.
During the prelocking phase, the variable 'trg_event_map'
will not be set for the view table. This value will be set
after the processing of triggers defined on the table. During
the processing of sub-statements, 'locked_tables_mode' will be
set to 'LTM_PRELOCKED' which denotes that further locking
of tables/functions cannot be done. This results in the other
table not being locked and thus further processing results in
an error getting reported.
FIX:
====
During the prelocking of view, the value of 'trg_event_map'
of the view is copied to 'trg_event_map' of the next table
in the TABLE_LIST. This results in the locking of tables
associated with the trigger as well.
This bug revealed a serious problem: if the same partition list
was used in two window specifications then the temporary table created
to calculate window functions contained fields for two identical
partitions. This problem was fixed as well.
Window functions need to have their own column in the work (temp) table,
like aggregate functions do.
They don't need val_int() -> val_int_result() conversion though, so they
should be wrapped with Item_direct_ref, not Item_aggregate_ref.
This fix also fixes a connection hang when trying to do INSERT DELAYED to a crashed table.
Added crash_mysqld.inc to allow easy crash+restart of mysqld
filesort and init_read_record() for the same table.
This will simplify code for WINDOW FUNCTIONS (MDEV-6115)
- Filesort_info renamed to SORT_INFO and moved to filesort.h
- filesort now returns SORT_INFO
- init_read_record() now takes a SORT_INFO parameter.
- unique declaration is moved to uniques.h
- subselect caching of buffers is now more explicit than before
- filesort_buffer is now reusable even if rec_length has changed.
- filsort_free_buffers() and free_io_cache() calls are removed
- Remove one malloc() when using get_addon_fields()
Other things:
- Added --debug-assert-on-not-freed-memory option to make it easier to
debug some not-freed-memory issues.
- Item_sum_count::remove() should check if the argument's value is NULL.
- Window Function item must have its Item_window_func::split_sum_func
called,
- and it must call split_sum_func for aggregate's arguments (see the
comment near Item_window_func::split_sum_func for explanation why)
"Re-factor the code for post-join operations".
The patch mainly contains the code ported from mysql-5.6 and
created for two essential architectural changes:
1. WL#5558: Resolve ORDER BY execution method at the optimization stage
2. WL#6071: Inline tmp tables into the nested loops algorithm
The first task was implemented for mysql-5.6 by Ole John Aske.
It allows to make all decisions on ORDER BY operation at the optimization
stage.
The second task implemented for mysql-5.6 by Evgeny Potemkin adds JOIN_TAB
nodes for post-join operations that require temporary tables. It allows
to execute these operations within the nested loops algorithm that used to
be used before this task only for join queries. Besides these task moves
all planning on the execution of these operations from the execution phase
to the optimization phase.
Some other re-factoring changes of mysql-5.6 were pulled in, mainly because
it was easier to pull them in than roll them back. In particular all
changes concerning Ref_ptr_array were incorporated.
The port required some changes in the MariaDB code that concerned the
functionality of EXPLAIN and ANALYZE. This was done mainly by Sergey
Petrunia.
Creating a CONNECT object on client connect and pass this to the working thread which creates the THD.
Split LOCK_thread_count to different mutexes
Added LOCK_thread_start to syncronize threads
Moved most usage of LOCK_thread_count to dedicated functions
Use next_thread_id() instead of thread_id++
Other things:
- Thread id now starts from 1 instead of 2
- Added cast for thread_id as thread id is now of type my_thread_id
- Made THD->host const (To ensure it's not changed)
- Removed some DBUG_PRINT() about entering/exiting mutex as these was already logged by mutex code
- Fixed that aborted_connects and connection_errors_internal are counted in all cases
- Don't take locks for current_linfo when we set it (not needed as it was 0 before)
Don't compare "field == table->next_number_field" because the field
can be special nullable field copy created by the trigger.
Compare field_index values instead.
NOT NULL constraint must be checked *after* the BEFORE triggers.
That is for INSERT and UPDATE statements even NOT NULL fields
must be able to store a NULL temporarily at least while
BEFORE INSERT/UPDATE triggers are running.
* move common code to a new set_bad_null_error() function
* move repeated comparison out of the loop
* remove unused code
* unused method Table_triggers_list::set_table
* redundant condition (if (table) after table was dereferenced)
* add an assert
On shutdown feedback was sending a short report without creating
a THD. At that point current_thd was pointing to the already
destroyed THD from the previous full report.
backport from 10.1:
commit bfe703a
Author: Sergei Golubchik <serg@mariadb.org>
Date: Tue Feb 3 18:19:56 2015 +0100
don't let current_thd to point to a destroyed THD
