The problems were that:
1) resources was freed "asimetric" normal execution in send_eof,
in case of error in destructor.
2) destructor was not called in case of SP for result objects.
(so if the last SP execution ended with error resorces was not
freeded on reinit before execution (cleanup() called before next
execution) and destructor also was not called due to lack of
delete call for the object)
Result cleanup() renamed to reset_for_next_ps_execution() to better
reflect function().
All result method revised and freeing resources made "symetric".
Destructor of result object called for SP.
Added skipped invalidation in case of error in insert.
Removed misleading naming of reset(thd) (could be mixed with
with reset()).
When UNION ALL is used with LIMIT ROWS EXAMINED, and when the limit is
exceeded for a SELECT that is not the last in the UNION, interrupt the
execution and call end_eof on the result. This makes sure that the
results are sent, and the query result status is conclusive rather
than empty, which would cause an assertion failure.
on disable_indexes(HA_KEY_SWITCH_NONUNIQ_SAVE) the engine does
not know that the long unique is logically unique, because on the
engine level it is not. And the engine disables it,
Change the disable_indexes/enable_indexes API. Instead of the enum
mode, send a key_map of indexes that should be enabled. This way the
server will decide what is unique, not the engine.
Found memory leaks were introduced by the commit
a896bebfa6
MDEV-18844 Implement EXCEPT ALL and INTERSECT ALL operations
and caused by using a statement arena instead a runtime arena for
allocation of objects having temporary life span by their nature.
Aforementioned memory leaks were produced by running queries
that typically use select with intersect, union or table values
constructors.
To fix these memory leaks use the runtime arena for allocation
of Item_field objects used by set operations.
Additionally, OOM handling added on allocation of aforementioned
Item_field objects.
This patch fixes the issue with passing the DEFAULT or IGNORE values to
positional parameters for some kind of SQL statements to be executed
as prepared statements.
The main idea of the patch is to associate an actual value being passed
by the USING clause with the positional parameter represented by
the Item_param class. Such association must be performed on execution of
UPDATE statement in PS/SP mode. Other corner cases that results in
server crash is on handling CREATE TABLE when positional parameter
placed after the DEFAULT clause or CALL statement and passing either
the value DEFAULT or IGNORE as an actual value for the positional parameter.
This case is fixed by checking whether an error is set in diagnostics
area at the function pack_vcols() on return from the function pack_expression()
This patch also fixes some bugs detected by valgrind after this
patch:
- Not enough copy_func elements was allocated by Create_tmp_table() which
causes an memory overwrite in Create_tmp_table::add_fields()
I added an ASSERT() to be able to detect this also without valgrind.
The bug was that TMP_TABLE_PARAM::copy_fields was not correctly set
when calling create_tmp_table().
- Aria::empty_bits is not allocated if there is no varchar/char/blob
fields in the table. Fixed code to take this into account.
This cannot cause any issues as this is just a memory access
into other Aria memory and the content of the memory would not be used.
- Aria::last_key_buff was not allocated big enough. This may have caused
issues with rtrees and ma_extra(HA_EXTRA_REMEMBER_POS) as they
would use the same memory area.
- Aria and MyISAM didn't take extended key parts into account, which
caused problems when copying rec_per_key from engine to sql level.
- Mark asan builds with 'asan' in version strihng to detect these in
not_valgrind_build.inc.
This is needed to not have main.sp-no-valgrind fail with asan.
select_union_direct::send_data() only sends a record when
the LIMIT ... OFFSET clause of the individual select won't skip it.
Thus, select_union_direct::send_data() should not do any actions
related to a sending a record if the offset of a select isn't
reached yet
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.
When creating a recursive CTE, the column types are taken from the
non recursive part of the CTE (this is according to the SQL standard).
This patch adds code to abort the CTE if the calculated values in the
recursive part does not fit in the fields in the created temporary table.
The new code only affects recursive CTE, so it should not cause any notable
problems for old applications.
Other things:
- Fixed that we get correct row numbers for warnings generated with
WITH RECURSIVE
Reviewer: Alexander Barkov <bar@mariadb.com>
from view
A crash of the server happened when executing a stored procedure whose the
only query calculated window functions over a mergeable view specified
as a select from non-mergeable view. The crash could be reproduced if
the window specifications of the window functions were identical and both
contained PARTITION lists and ORDER BY lists. A crash also happened on
the second execution of the prepared statement created for such query.
If to use derived tables or CTE instead of views the problem still
manifests itself crashing the server.
When optimizing the window specifications of a window function the
server can substitute the partition lists and the order lists for
the corresponding lists from another window specification in the case
when the lists are identical. This substitution is not permanent and should
be rolled back before the second execution. It was not done and this
ultimately led to a crash when resolving the column names at the second
execution of SP/PS.
The bug affected execution of queries with With clauses containing so-called
hanging recursive CTEs in PREPARE mode. A CTE is hanging if it's not used
in the query. Preparation of a prepared statement from a query with a
hanging CTE caused a leak in the server and execution of this prepared
statement led to an assert failure of the server built in the debug mode.
This happened because the units specifying recursive CTEs erroneously were
not cleaned up if those CTEs were hanging.
The patch enforces cleanup of hanging recursive CTEs in the same way as
other hanging CTEs.
Approved by dmitry.shulga@mariadb.com
This bug could cause a crash when executing queries that used mutually
recursive CTEs with system variable big_tables set to 1. It happened due
to several bugs in the code that handled recursive table references
referred mutually recursive CTEs. For each recursive table reference a
temporary table is created that contains all rows generated for the
corresponding recursive CTE table on the previous step of recursion.
This temporary table should be created in the same way as the temporary
table created for a regular materialized derived table using the
method select_union::create_result_table(). In this case when the
temporary table is created it uses the select_union::TMP_TABLE_PARAM
structure as the parameter for the table construction. However the
code created the temporary table using just the function create_tmp_table()
and passed pointers to certain fields of the TMP_TABLE_PARAM structure
used for accumulation of rows of the recursive CTE table as parameters
for update. This was a mistake because now different temporary tables
cannot share some TMP_TABLE_PARAM fields in a general case. Besides,
depending on how mutually recursive CTE tables were defined and which
of them were referred in the executed query the select_union object
allocated for a recursive table reference could be allocated again after
the the temporary table had been created. In this case the TMP_TABLE_PARAM
object associated with the temporary table created for the recursive
table reference contained unassigned fields needed for execution when
Aria engine is employed as the engine for temporary tables.
This patch ensures that
- select_union object is created only once for any recursive table
reference
- any temporary table created for recursive CTEs uses its own
TMP_TABLE_PARAM structure
The patch also fixes a problem caused by incomplete cleanup of join tables
associated with recursive table references.
Approved by Oleksandr Byelkin <sanja@mariadb.com>
When executing set operations in a pipeline using only one temporary table
additional scans of intermediate results may be needed. The scans are
performed with usage of the rnd_next() handler function that might
leave record buffers used for the temporary table not in a state that
is good for following writes into the table. For example it happens for
aria engine when the last call of rnd_next() encounters only deleted
records. Thus a cleanup of record buffers is needed after each such scan
of the temporary table.
Approved by Oleksandr Byelkin <sanja@mariadb.com>
in TABLE_LIST::is_recursive_with_tables
After the patch for MDEV-23619 the code of st_select_lex::cleanup started
using the list st_select_lex::leaf_tables. This list is built for any
query with FROM clause in the function setup_tables(). If such query is
used in a stored procedure it must be ensured that the list is empty
before each new call of the procedure. Otherwise if the first call of
the procedure is successful while the second call reports an error before
the setup_tables() is invoked then list st_select_lex::leaf_tables would
point to a piece of memory that has been already freed.
Approved by Oleksandr Byelkin <sanja@mariadb.com>
Due to a premature cleanup of the unit that specified a recursive CTE
used in the second operand of union the server fell into an infinite
loop in the reported test case. In other cases this premature cleanup
could cause other problems.
The bug is the result of a not quite correct fix for MDEV-17024. The
unit that specifies a recursive CTE has to be cleaned only after the
cleanup of the last external reference to this CTE. It means that
cleanups of the unit triggered not by the cleanup of a external
reference to the CTE must be blocked.
Usage of local table chains in selects to get external references to
recursive CTEs was not correct either because of possible merges of
some selects.
Also fixed a minor bug in st_select_lex::set_explain_type() that caused
typing 'RECURSIVE UNION' instead of 'UNION' in EXPLAIN output for external
references to a recursive CTE.
Removing the ORDER BY clause from the UNION when UNION is inside an IN/ALL/ANY/EXISTS subquery.
The rewrites are done for subqueries but this rewrite is not done for the fake_select of
the UNION.
This bug is the same as the bug MDEV-17024. The crashes caused by these
bugs were due to premature cleanups of the unit specifying recursive CTEs
that happened in some cases when there were several outer references the
same recursive CTE.
The problem of premature cleanups for recursive CTEs could be already
resolved by the correction in TABLE_LIST::set_as_with_table() introduced
in this patch. ALL other changes introduced by the patches for MDEV-17024
and MDEV-22748 guarantee that this clean-ups are performed as soon as
possible: when the select containing the last outer reference to a
recursive CTE is being cleaned up the specification of the recursive CTE
should be cleaned up as well.
MDEV-19964 S3 replication support
Added new configure options:
s3_slave_ignore_updates
"If the slave has shares same S3 storage as the master"
s3_replicate_alter_as_create_select
"When converting S3 table to local table, log all rows in binary log"
This allows on to configure slaves to have the S3 storage shared or
independent from the master.
Other thing:
Added new session variable '@@sql_if_exists' to force IF_EXIST to DDL's.
