`WSREP_CLIENT` is used as condition for starting ALTER/OPTIMIZE/REPAIR TOI.
Using this condition async replicated affected DDL's will not be replicated.
Fixed by removing this condition.
Reviewed-by: Jan Lindström <jan.lindstrom@mariadb.com>
This patch makes the following changes around variable wsrep_on:
1) Variable wsrep_on can no longer be updated from a session that has
an active transaction running. The original behavior allowed cases
like this:
BEGIN;
INSERT INTO t1 VALUES (1);
SET SESSION wsrep_on = OFF;
INSERT INTO t1 VALUES (2);
COMMIT;
With regular transactions this would result in no replication
events (not even value 1). With streaming replication it would be
unnecessarily complex to achieve the same behavior. In the above
example, it would be possible for value 1 to be already replicated if
it happened to fill a separate fragment, while value 2 wouldn't.
2) Global variable wsrep_on no longer affects current sessions, only
subsequent ones. This is to avoid a similar case to the above, just
using just by using global wsrep_on instead session wsrep_on:
--connection conn_1
BEGIN;
INSERT INTO t1 VALUES(1);
--connection conn_2
SET GLOBAL wsrep_on = OFF;
--connection conn_1
INSERT INTO t1 VALUES(2);
COMMIT;
The above example results in the transaction to be replicated, as
global wsrep_on will only affect the session wsrep_on of new
connections.
Reviewed-by: Jan Lindström <jan.lindstrom@mariadb.com>
../sql/spatial.cc: In member function ‘double Gis_point::calculate_haversine(const Geometry*, double, int*)’:
../sql/spatial.cc:1093:45: error: ‘y1r’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
1093 | res= 2*sphere_radius*asin((sqrt(dlat + cos(y1r)*cos(y2r)*dlong)));
| ~~~^~~~~
../sql/spatial.cc:1092:20: error: ‘x1r’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
1092 | dlong= sin((x2r - x1r)/2)*sin((x2r - x1r)/2);
| ~~~~~^~~~~~
../sql/spatial.cc:1093:54: error: ‘y2r’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
1093 | res= 2*sphere_radius*asin((sqrt(dlat + cos(y1r)*cos(y2r)*dlong)));
| ~~~^~~~~
../sql/spatial.cc:1092:20: error: ‘x2r’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
1092 | dlong= sin((x2r - x1r)/2)*sin((x2r - x1r)/2);
| ~~~~~^~~~~~
c
Add condition on trx->state == TRX_STATE_COMMITTED_IN_MEMORY in order to
avoid unnecessary work. If a transaction has already been committed or
rolled back, it will release its locks in lock_release() and let
the waiting thread(s) continue execution.
Let BF wait on lock_rec_has_to_wait and if necessary other BF
is replayed.
wsrep_trx_order_before
If BF is not even replicated yet then they are ordered
correctly.
bg_wsrep_kill_trx
Make sure victim_trx is found and check also its state. If
state is TRX_STATE_COMMITTED_IN_MEMORY transaction is
already committed or rolled back and will release it locks
soon.
wsrep_assert_no_bf_bf_wait
Transaction requesting new record lock should be TRX_STATE_ACTIVE
Conflicting transaction can be in states TRX_STATE_ACTIVE,
TRX_STATE_COMMITTED_IN_MEMORY or in TRX_STATE_PREPARED.
If conflicting transaction is already committed in memory or
prepared we should wait. When transaction is committed in memory we
held trx mutex, but not lock_sys->mutex. Therefore, we
could end here before transaction has time to do lock_release()
that is protected with lock_sys->mutex.
lock_rec_has_to_wait
We very well can let bf to wait normally as other BF will be
replayed in case of conflict. For debug builds we will do
additional sanity checks to catch unsupported bf wait if any.
wsrep_kill_victim
Check is victim already in TRX_STATE_COMMITTED_IN_MEMORY state and
if it is we can return.
lock_rec_dequeue_from_page
lock_rec_unlock
Remove unnecessary wsrep_assert_no_bf_bf_wait function calls.
We can very well let BF wait here.
`mallinfo` is deprecated since glibc 2.33 and has been replaced by mallinfo2.
The deprecation causes building the server to fail if glibc version is > 2.33.
Check if mallinfo2 exist on the system and use it instead.
Binlog group commit could lead to a situation where group commit leader
accesses participant thd's wsrep client state concurrently with the
thread executing the participant thd.
This is because of race condition in
MYSQL_BIN_LOG::write_transaction_to_binlog_events(),
and was fixed by moving wsrep_ordered_commit() to happen in
MYSQL_BIN_LOG::queue_for_group_commit() under protection of
LOCK_prepare_ordered mutex.
splittable derived
If one of joined tables of the processed query is a materialized derived
table (or view or CTE) with GROUP BY clause then under some conditions it
can be subject to split optimization. With this optimization new equalities
are injected into the WHERE condition of the SELECT that specifies this
derived table. The injected equalities are generated for all join orders
with which the split optimization can employed. After the best join order
has been chosen only certain of this equalities are really needed. The
others can be safely removed. If it's not done and some of injected
equalities involve expressions over semi-joins with look-up access then
the query may return a wrong result set.
This patch effectively removes equalities injected for split optimization
that are needed only at the optimization stage and not needed for execution.
Approved by serg@mariadb.com
by compound index
This typo bug may lead to wrong result sets for equi-join queries where
the join operation is supported by a compound index such that the order of
its components differs from the order of the corresponding columns in
the table the index belongs to. The bug manifests itself only when usage
of the BNLH algorithm is forced.
The fix for the bug was provided by Chu Huaxing.
in ON condition
The fix of the bug MDEV-25002 for 10.4 turned out to be incomplete. It
caused crashes when executing CREATE VIEW, CREATE TABLE .. SELECT,
INSERT .. SELECT statements if their SELECTs contained references to
non-existing fields.
This patch complements the fix for MDEV-25002 in order to avoid such
crashes.
Approved by Oleksandr Byelkin <sanja@mariadb.com>
If a query with implicit grouping contains in MIN/MAX set function in the
select list over a column that is a part of an index then the query
might be subject to MIN/MAX optimization. With this optimization the
server performs a look-up into an index, fetches a value of the column C
used in the MIN/MAX function and substitute the MIN/MAX expression for this
value. This allows to eliminate the table containing C from further join
processing. In order the optimization to be applied the WHERE condition
must be a conjunction of simple equality/inequality predicates or/and
BETWEEN predicates.
The bug fixed in the patch resulted in fetching a wrong value from the
index used for MIN/MAX optimization. It may happened when a BETWEEN
predicate containing the MIN/MAX value followed a strict inequality.
Approved by dmitry.shulga@mariadb.com
Store old value of binlog format before wsrep code so that
if we bail out because wsrep is not ready for connections
we can restore binlog format correctly.
Store old value of binlog format before wsrep code so that
if we bail out because wsrep is not ready for connections
we can restore binlog format correctly.
The query causing the issue here has implicit grouping for we
have to produce one row with special values for the aggregates
(depending on each aggregate function), and NULL values for all
non-aggregate fields.
The subselect item where implicit grouping was being done,
null_value for the subselect item was not being set for
the case when the implicit grouping produces NULL values
for the items in the select list of the subquery.
This which was leading to the crash.
The fix would be to set the null_value when all the values
for the row column have NULL values.
Further changes are
1) etting null_value for Item_singlerow_subselect only
after val_* functions have been called.
2) Introduced a parameter null_value_inside to Item_cache that
would store be set to TRUE if any of the arguments of the
Item_cache are null.
Reviewed And co-authored by Monty
This bug manifested itself when executing queries with multiple reference
to a CTE specified by a query expression with union and having its
column names explicitly declared. In this case the server returned a bogus
error message about unknown column name. It happened because while for the
first reference to the CTE the names of the columns returned by the CTE
specification were properly changed to match the CTE definition for the
other references it was not done. This was a consequence of not quite
complete code of the function With_element::clone_parsed_spec() that forgot
to set the reference to the CTE definition for unit structures representing
non-first CTE references.
Approved by dmitry.shulga@mariadb.com
This bug could affect multi-way join queries with embedded outer joins that
contained a conjunctive IS NULL predicate over a non-nullable column from
inner table of an outer join. The predicate could occur in WHERE condition
or in ON condition. Due to this bug a wrong result set could be returned by
the query. The bug manifested itself only when join buffers were employed
for join operations.
The problem appeared because
- a bug in the function JOIN_CACHE::get_match_flag_by_pos that not always
returned proper match flags for embedding outer joins stored together
with table rows put a join buffer.
- bug in the function JOIN_CACHE::join_matching_records that not always
correctly determined that a row from the buffer could be skipped due
to applied 'not_exists' optimization.
Example:
SELECT * FROM t1 LEFT JOIN ((t2 LEFT JOIN t3 ON c = d) JOIN t4) ON b = e
WHERE e IS NULL;
The patch introduces a new function that finds the match flag for a record
from join buffer specifying the buffer where this flag has to be found.
The function is called JOIN_CACHE::get_match_flag_by_pos_from_join_buffer().
Now this function rather than JOIN_CACHE::get_match_flag_by_pos() is used
in JOIN_CACHE::skip_if_matched() to check whether a record from the join
buffer must be ignored when extending the record by null complements.
Also the code of the function JOIN_CACHE::skip_if_not_needed_match() has
been changed. The function checks whether a record from the join buffer
still may produce some useful extensions.
Also some clarifying comments has been added.
Approved by monty@mariadb.com.
It was possibile for a user to create an interlocked state which may go on
for a significant period of time. There is a tight loop in the FTWRL code
path that tries to repeatedly acquire a read lock. As the weight of FTWRL
lock is the smallest among others, it's always selected by the deadlock
detector, but can never be killed.
Imaging the following sequence:
connection_0 connection_1
GET_LOCK("l1", 0);
LOCK TABLES t WRITE;
FLUSH TABLES WITH READ LOCK;
GET_LOCK("l1", 1000);
The GET_LOCK statement in connection_1 triggers the deadlock detector,
which tries to select the lock in FTWRL, since its weight is 0. However,
since a loop in Global_read_lock::lock_global_read_lock() tries to always
win, it tries to acquire lock again. Which invokes the deadlock detector,
and that cycle continues until GET_LOCK in connection_1 times out.
This patch resolves the live-locking by introducing a dynamic bonus to the
deadlock weight associated with every lock. Each lock gets a bonus weight
each time it's selected by the deadlock detector. In case of a live-lock
situation, those locks that cannot be killed, get additional weight each
iteration. Eventually their weight becomes so high that the deadlock
detector shifts its attention to other lock, until it find the one that
can be killed.
A bogus error message was issued for any outer references occurred in
ON expressions used in subqueries. This prevented execution of queries
containing subqueries as soon as they used outer references in their ON
clauses. This happened because the Name_resolution_context structure
created for any ON expression erroneously had the field outer_context set
to NULL. The fields select_lex of this structure was not set correctly
either.
The idea of the fix was taken from mysql code of the function
push_new_name_resolution_context().
Approved by dmitry.shulga@mariadb.com
optimize_schema_tables_memory_usage() crashed when its argument included
TABLE struct that was not fully initialized.
To prevent such a crash, we check if a table is an information schema table at
the beginning of each iteration.
Closes#1768
if a query used no fields from an I_S table, we were creating a temp
table with one, first, field (as a table cannot have zero fields),
with its length truncated to 1.
Now - force also this dummy field to be a normal field, not a BLOB
Incorrect processing of an auto-incrementing field in the
WSREP-related code during applying transactions results in
a duplicate key being created. This is due to the fact that
at the beginning of the write_row() and update_row() functions,
the values of the auto-increment parameters are used, which
are read from the parameters of the current thread, but further
along the code other values are used, which are read from global
variables (when applying a transaction). This can happen when
the cluster configuration has changed while applying a transaction
(for example in the high_priority_service mode for Galera 4).
Further during IST processing duplicating key is detected, and
processing of the DB_DUPLICATE_KEY return code (inside innodb,
in the write_row() handler) results in a call to the
wsrep_thd_self_abort() function.
row_number() over () window function can be used without any column in the OVER
clause. Additionally, the item doesn't reference any tables, as it's not
effectively referencing any table. Rather it is specifically built based
on the end temporary table used for window function computation.
This caused remove_const function to wrongly drop it from the ORDER
list. Effectively, we shouldn't be dropping any window function from the
ORDER clause, so adjust remove_const to account for that.
Reviewed by: Sergei Petrunia sergey@mariadb.com
