and also MDEV-25564, MDEV-18157.
Attempt to produce EXPLAIN output caused a crash in
Explain_node::print_explain_for_children. The cause of this was that an
Explain_node (actually a derived) had a link to child select#N, but
there was no query plan present for select#N.
The query plan wasn't present because the subquery was eliminated.
- Either it was a degenerate subquery like "(SELECT 1)" in MDEV-25564.
- Or it was a subquery in a UNION subquery's ORDER BY clause:
col IN (SELECT ... UNION
SELECT ... ORDER BY (SELECT FROM t1))
In such cases, legacy code structure in subquery/union processing code(*)
makes it hard to detect that the subquery was eliminated, so we end up
with EXPLAIN data structures (Explain_node::children) having dangling
links to child subqueries.
Do make the checks and don't follow the dangling links.
(In ideal world, we should not have these dangling links. But fixing
the code (*) would have high risk for the stable versions).
The population of default values in INSERT SELECT was being
performed twice. With sequences, this resulted in every
second sequence value being used.
With SELECT INSERT we remove the second invokation of
table->update_default_fields(). This was already performed
in store_values() invoking fill_record_n_invoke_before_triggers()
which invoked update_default_fields() previously.
We do need to return an error on duplicate values, so the
::store_values is extended to take the ignore option.
=========== Problem =============
- `show columns` is not working for temporary tables, even though there
is enough privilege `create temporary tables`.
=========== Solution =============
- Append `TMP_TABLE_ACLS` privilege when running `show columns` for temp
tables.
- Additionally `check_access()` for database only once, not for each
field
=========== Additionally =============
- Update comments for function `check_table_access` arguments
Reviewed by: <vicentiu@mariadb.org>
For some queries that involve tables with different but convertible
character sets for columns taking part in the query, repeatable
execution of such queries in PS mode or as part of a stored routine
would result in server abnormal termination.
For example,
CREATE TABLE t1 (a2 varchar(10));
CREATE TABLE t2 (u1 varchar(10) CHARACTER SET utf8);
CREATE TABLE t3 (u2 varchar(10) CHARACTER SET utf8);
PREPARE stmt FROM
"SELECT t1.* FROM (t1 JOIN t2 ON (t2.u1 = t1.a2))
WHERE (EXISTS (SELECT 1 FROM t3 WHERE t3.u2 = t1.a2))";
EXECUTE stmt;
EXECUTE stmt; <== Running this prepared statement the second time
results in server crash.
The reason of server crash is that an instance of the class
Item_func_conv_charset, that created for conversion of a column
from one character set to another, is allocated on execution
memory root but pointer to this instance is stored in an item
placed on prepared statement memory root. Below is calls trace to
the place where an instance of the class Item_func_conv_charset
is created.
setup_conds
Item_func::fix_fields
Item_bool_rowready_func2::fix_length_and_dec
Item_func::setup_args_and_comparator
Item_func_or_sum::agg_arg_charsets_for_comparison
Item_func_or_sum::agg_arg_charsets
Item_func_or_sum::agg_item_set_converter
Item::safe_charset_converter
And the following trace shows the place where a pointer to
the instance of the class Item_func_conv_charset is passed
to the class Item_func_eq, that is created on a memory root of
the prepared statement.
Prepared_statement::execute
mysql_execute_command
execute_sqlcom_select
handle_select
mysql_select
JOIN::optimize
JOIN::optimize_inner
convert_join_subqueries_to_semijoins
convert_subq_to_sj
To fix the issue, switch to the Prepared Statement memory root
before calling the method Item_func::setup_args_and_comparator
in order to place any created Items on permanent memory root.
It may seem that such approach would result in a memory
leakage in case the parameter marker '?' is used in the query
as in the following example
PREPARE stmt FROM
"SELECT t1.* FROM (t1 JOIN t2 ON (t2.u1 = t1.a2))
WHERE (EXISTS (SELECT 1 FROM t3 WHERE t3.u2 = ?))";
EXECUTE stmt USING convert('A' using latin1);
but it wouldn't since for such case any of the parameter markers
is treated as a constant and no subquery to semijoin optimization
is performed.
See also commits aa8a31da and 64678c for a Bug #22990029 fix.
In this scenario INSERT chose to check if delete unmarking is available for
a just deleted record. To build an update vector, it needed to calculate
the vcols as well. Since this INSERT was not IGNORE-flagged, recalculation
failed.
Solutiuon: temporarily set abort_on_warning=true, while calculating the
column for delete-unmarked insert.
As of now innodb does not store trx_id for each record in secondary index.
The idea behind is following: let us store only per-page max_trx_id, and
delete-mark the records when they are deleted/updated.
If the read starts, it rememders the lowest id of currently active
transaction. Innodb refers to it as trx->read_view->m_up_limit_id.
See also ReadView::open.
When the page is fetched, its max_trx_id is compared to m_up_limit_id.
If the value is lower, and the secondary index record is not delete-marked,
then this page is just safe to read as is. Else, a clustered index could be
needed ato access. See page_get_max_trx_id call in row_search_mvcc, and the
corresponding switch (row_search_idx_cond_check(...)) below.
Virtual columns are required to be updated in case if the record was
delete-marked. The motivation behind it is documented in
Row_sel_get_clust_rec_for_mysql::operator() near
row_sel_sec_rec_is_for_clust_rec call.
This was basically a description why virtual column computation can
normally happen during SELECT, and, generally, a vcol index access.
Sometimes stats tables are updated by innodb. This starts a new
transaction, and it can happen that it didn't finish to the moment of
SELECT execution, forcing virtual columns recomputation. If the result was
a something that normally outputs a warning, like division by zero, then
it could be outputted in a racy manner.
The solution is to suppress the warnings when a column is computed
for the described purpose.
ignore_wrnings argument is added innobase_get_computed_value.
Currently, it is only true for a call from
row_sel_sec_rec_is_for_clust_rec.
When f.ex. table is partitioned by HASH(a) and we rename column `a' to
`b' partitioning filter stays unchanged: HASH(a). That's the wrong
behavior.
The patch updates partitioning filter in accordance to the new columns
names. That includes partition/subpartition expression and
partition/subpartition field list.
Let us disable Valgrind on tests that would fail because a
server shutdown or a STOP SLAVE command would take longer,
causing the test harness to forcibly and silently kill the server
due to an exceeded timeout.
row_purge_get_partial(): Replaces trx_undo_rec_get_partial_row().
Also copy the purge_node_t::ref to the purge_node_t::row.
In this way, the clustered index key fields will always be
available, even if thanks to
commit d384ead0f0 (MDEV-14799)
they would no longer be repeated in the remaining part of the
undo log record.
This commit adds automation that will reduce the possibility
of user errors when customizing wsrep_notify.sh (in particular
caused by user-specified parameters). Now all leading and trailing
spaces are removed from the user-specified parameters and automatic
port and host address substitution has been added to scripts, as
well as automatic password substitution to the client command line,
only if it is specified in the wsrep_notify.sh and not as empty
strings. Also added support for automatic substitution of the all
SSL-related parameters and improved parsing for ipv6 addresses
(to allow "[...]" notation for ipv6 addresses). Also added a
test to check if the wsrep notify script will works with SSL.
The problem is that if table definition cache (TDC) is full of real tables
which are in tables cache, view definition can not stay there so will be
removed by its own underlying tables.
In situation above old mechanism of detection matching definition in PS
and current version always require reprepare and so prevent executing
the PS.
One work around is to increase TDC, other - improve version check for
views/triggers (which is done here). Now in suspicious cases we check:
- timestamp (microseconds) of the view to be sure that version really
have changed;
- time (microseconds) of creation of a trigger related to time
(microseconds) of statement preparation.
- Added missing information about database of corresponding table for various types of commands
- Update some typos
- Reviewed by: <vicentiu@mariadb.org>
This patch resolves the problem of improper name resolution of table
references to embedded CTEs for some queries. This improper binding could
lead to
- infinite sequence of calls of recursive functions
- crashes due to resolution of null pointers
- wrong result sets returned by queries
- bogus error messages
If the definition of a CTE contains with clauses then such CTE is called
embedding CTE while CTEs from the with clauses are called embedded CTEs.
If a table reference used in the definition of an embedded CTE cannot be
resolved within the unit that contains this reference it still may be
resolved against a CTE definition from the with clause with one of the
embedding CTEs.
A table reference can be resolved against a CTE definition if it used in
the the scope of this definition and it refers to the name of the CTE.
Table reference t is in the scope of the CTE definition of CTE cte if
- the definition of cte is an element of a with clause declared as
RECURSIVE and the reference t belongs either to the unit to which
this with clause is attached or to one of the elements of this clause
- the definition of cte is an element of a with clause without RECURSIVE
specifier and the reference t belongs either to the unit to which this
with clause is attached or to one of the elements from this clause that
are placed before the definition of cte.
If a table reference can be resolved against several CTE definitions then
it is bound to the most embedded.
The code before this patch not always resolved table references used in
embedded CTE according to the above rules.
Approved by Oleksandr Byelkin <sanja@mariadb.com>
Nowdays subquery in a UNION's ORDER BY placed correctly in fake select,
the only problem was incorrect Name_resolution_contect is fixed by this
patch in parsing, so we do not need scanning/reseting of ORDER BY of
a union.
Tests with checking metadata or that cannot be run with
the view-protocol are excluded from --view-protocol.
For tests that do not allow the use of an additional connection,
the util connection is disabled with "--disable_service_connection".
Also cases with bugs for --view-protocol are disabled.
row_log_table_apply_update(): Free the pcur.old_rec_buf before returning.
It may be allocated by btr_pcur_store_position() inside
btr_blob_log_check_t::check() and btr_store_big_rec_extern_fields().
This memory leak was introduced in
commit 2e814d4702 (MariaDB Server 10.2.2)
via mysql/mysql-server@ce0a1e85e2
(MySQL 5.7.5).
The rpl_row_img_sequence test can fail on resource
constrained buildbot machines due to its high
space consumption. To reduce this footprint, the
test is split into three parts, one for each value
of the binlog_row_img variable.
The issue manifests due to a bug in mysql_routine_grant. This was a side
effect of e46eea8660 which fixed the problem of not giving appropriate error
message (ER_NONEXISTING_PROC_GRANT) when a routine grant existed due to role
inheritance.
When granting a routine privilege, it is possible to have a GRANT_NAME
entry already created from an inherited role, but with it's init_privs
set to 0.
In this case we must not create a *new* grant entry, but we must edit
this grant entry to set its init_privs.
Note that this case was already covered by MDEV-29458, however due to a
forgotten "flush privileges;" the actual code path never got hit.
Remove the flush privilege command as it was never intended to be there
in the first place.
There was an issue in updating in-memory role datastructures when
propagating role grants.
The issue is that changing a particular role's privilege (on any
privilege level, global, database, etc.)
was done such that it overwrote the entire set of bits for that
particular level of privileges.
For example:
grant select on *.* to r1 -> sets the access bits to r1 to select,
regardless of what bits were present for role r1 (inherited from any
other roles).
Before this fix, the rights of role r1 were propagated to any roles r1
was granted to, however the propagated rights did *not* include the
complete rights r1 inherited from its own grants.
For example:
grant r2 to r1;
grant select on *.* to r2;
grant insert on *.* to r1; # This command completely disregards the
# select privilege from r2.
In order to correct this, ensure that before rights are propagated
onwards, that the current's role rights have been updated from its
grants.
Additionally, the patch exposed a flaw in the DROP ROLE code.
When deleting a role we removed all its previous grants, but what
remained was the actual links of roles granted to the dropped role.
Having these links present when propagating grants meant that we would
have leftover ACL_xxx entries.
Ensure that the links are removed before propagating grants.
There was a bug in the ACL internal data structures GRANT_TABLE and
GRANT_COLUMN. The semantics are: GRANT_TABLE::init_cols and
GRANT_COLUMN::init_privs represent the bits that correspond to the
privilege bits stored in the physical tables. The other struct members
GRANT_TABLE::cols and GRANT_COLUMN::privs represent the actual access
bits, as they may be modified through role grants.
The error in logic was mixing the two fields and thus we ended up
storing the logical access bits in the physical tables, instead of the
physical (init_xxx) bits.
This caused subsequent DBUG_ASSERT failures when dropping the involved
roles.
btr_lift_page_up(): If the leaf page only contains a hidden metadata
record for MDEV-11369 instant ADD COLUMN, convert the table to the
canonical format like we are supposed to do whenever the table
becomes empty.
lock_place_prdt_page_lock(): Do not place locks on temporary tables.
Temporary tables can only be accessed from one connection, so
it does not make any sense to acquire any transactional locks on them.
Use suspend thread syncpoint instead of include/wait_condition.inc to
make sure DELETE created waiting lock before the next UPDATE begins
locking.
This is backport of commit 0fa4dd0747
from 10.6.
- During shutdown, InnoDB fts fails to update synced doc id
when there is only one doc id about to sync. While starting
the server, InnoDB fetches the already synced doc id from
config table. In the subsequent sync operation, InnoDB fails
with DB_DUPLICATE_KEY error.
Problem:
========
Replication can break while applying a query log event if its
respective command errors on the primary, but is ignored by the
replication filter within Grant_tables on the replica. The bug
reported by MDEV-28530 shows this with REVOKE ALL PRIVILEGES using a
non-existent user. The primary will binlog the REVOKE command with
an error code, and the replica will think the command executed with
success because the replication filter will ignore the command while
accessing the Grant_tables classes. When the replica performs an
error check, it sees the difference between the error codes, and
replication breaks.
Solution:
========
If the replication filter check done by Grant_tables logic ignores
the tables, reset thd->slave_expected_error to 0 so that
Query_log_event::do_apply_event() can be made aware that the
underlying query was ignored when it compares errors.
Note that this bug also effects DROP USER if not all users exist
in the provided list, and the patch fixes and tests this case.
Reviewed By:
============
andrei.elkin@mariadb.com