In this issue we are using derived_with_keys optimization and we are using these keys to do a hash join which is incorrect.
We cannot create keys for dervied tables whose keyparts have types are of BLOB or TEXT type. TEXT or BLOB columns can only be
indexed over a specified length.
MDEV-14957: JOIN::prepare gets unusable "conds" as argument
Do not touch merged derived (it is irreversible)
Fix first argument of in_optimizer for calls possible before fix_fields()
In this case we were using the optimization derived_with_keys but we could not create a key
because the length of the key was greater than the max allowed(MI_MAX_KEY_LENGTH).
To do the join we needed to create a hash join key instead, but in the explain output it
showed that we were still referring to derived keys which were created but not used.
Also, implement MDEV-11027 a little differently from 5.5 and 10.0:
recv_apply_hashed_log_recs(): Change the return type back to void
(DB_SUCCESS was always returned).
Report progress also via systemd using sd_notifyf().
This patch is actually a complement for the fix of bug mdev-6892.
The procedure create_tmp_table() now must take into account
Item_direct_refs that wrap up constant fields of derived tables/views
that are used as inner tables in outer join operations.
Problem: Not all permanent Item_direct_view_ref was in permanent list of used items of the view.
Solution: Detect creating permenent view/derived table reference and put them in the permanent list at once.
Taking into account implicit dependence of constant view field from nullable table of left join added.
Fixed finding real table to check if it turned to NULL (materialized view & derived taken into account)
Removed incorrect uninitialization.
We have to run the derived table prepare before the unique table check to mark the derived table (in this case the unique table check can turn that table to materialized one).
THD::thd->activate_stmt_arena_if_needed() should be used to temporary activating statement arena instead of direct usage of THD::set_n_backup_active_arena() because possible such scenario:
1) func1 saves current arena and activates copy1 of statement arena
2) func2 saves copy1 of statement arena setup by func1 and activates copy2
3) some changes made for copy 2
4) func2 stores changed copy2 back to statenet arena and activates copy1
5) func1 store unchanged copy1 back to statemnt arena (rewrite changed copy 2 so changes become lost) and activates arena which was before.
sql/sql_insert.cc:
CREATE ... IF NOT EXISTS may do nothing, but
it is still not a failure. don't forget to my_ok it.
******
CREATE ... IF NOT EXISTS may do nothing, but
it is still not a failure. don't forget to my_ok it.
sql/sql_table.cc:
small cleanup
******
small cleanup
The following were missing in the patch for mwl106:
- KEY_PART_INFO::fieldnr were not set for generated keys to access
tmp tables storing the rows of materialized derived tables/views
- TABLE_SHARE::column_bitmap_size was not set for tmp tables storing
the rows of materialized derived tables/views.
These could cause crashes or memory overwrite.
The function simple_pred did not take into account that a multiple equality
could include ref items (more exactly items of the class Item_direct_view_ref).
It caused crashes for queries over derived tables or views if the
min/max optimization could be applied to these queries.
When looking for the execution plan of a derived table to be materialized
JOIN::optimize finds out that all joined tables of the derived table
contain not more than one row then the derived table should be maretialized
at the optimization stage.
Added a test case for the bug.
Adjusted results in other test cases.
- Fixed some issues with partitions and connection_string, which also fixed lp:716890 "Pre- and post-recovery crash in Aria"
- Fixed wrong assert in Aria
Now need to merge with latest xtradb before pushing
sql/ha_partition.cc:
Ensure that m_ordered_rec_buffer is not freed before close.
sql/mysqld.cc:
Changed to use opt_stack_trace instead of opt_pstack.
Removed references to pstack
sql/partition_element.h:
Ensure that connect_string is initialized
storage/maria/ma_key_recover.c:
Fixed wrong assert
temptable views
The TABLE::key_read field indicates if the optimizer has found that row
retrieval only should access the index tree. The triggered assert
inside close_thread_table() checks that this field has been reset when
the table is about to be closed.
During normal execution, these fields are reset right before tables are
closed at the end of mysql_execute_command(). But in the case of errors,
tables are closed earlier. The patch for Bug#52044 refactored the open
tables code so that close_thread_tables() is called immediately if
opening of tables fails. At this point in the execution, it could
happend that all TABLE::key_read fields had not been properly reset,
therefore triggering the assert.
The problematic statement in this case was EXPLAIN where the query
accessed two derived tables and where the first derived table was
processed successfully while the second derived table was not.
Since it was an EXPLAIN, TABLE::key_read fields were not reset after
successful derived table processing since the state needs to be
accessible afterwards. When processing of the second derived table
failed, it's corresponding SELECT_LEX_UNIT was cleaned, which caused
it's TABLE::key_read fields to be reset. Since processing failed,
the error path of open_and_lock_tables() was entered and
close_thread_tables() was called. The assert was then triggered due
to the TABLE::key_read fields set during processing of the first
derived table.
This patch fixes the problem by adding a new derived table processor,
mysql_derived_cleanup() that is called after mysql_derived_filling().
It causes cleanup of all SELECT_LEX_UNITs to be called, resetting
all relevant TABLE::key_read fields.
Test case added to derived.test.
--Bug#52157 various crashes and assertions with multi-table update, stored function
--Bug#54475 improper error handling causes cascading crashing failures in innodb/ndb
--Bug#57703 create view cause Assertion failed: 0, file .\item_subselect.cc, line 846
--Bug#57352 valgrind warnings when creating view
--Recently discovered problem when a nested materialized derived table is used
before being populated and it leads to incorrect result
We have several modes when we should disable subquery evaluation.
The reasons for disabling are different. It could be
uselessness of the evaluation as in case of 'CREATE VIEW'
or 'PREPARE stmt', or we should disable subquery evaluation
if tables are not locked yet as it happens in bug#54475, or
too early evaluation of subqueries can lead to wrong result
as it happened in Bug#19077.
Main problem is that if subquery items are treated as const
they are evaluated in ::fix_fields(), ::fix_length_and_dec()
of the parental items as a lot of these methods have
Item::val_...() calls inside.
We have to make subqueries non-const to prevent unnecessary
subquery evaluation. At the moment we have different methods
for this. Here is a list of these modes:
1. PREPARE stmt;
We use UNCACHEABLE_PREPARE flag.
It is set during parsing in sql_parse.cc, mysql_new_select() for
each SELECT_LEX object and cleared at the end of PREPARE in
sql_prepare.cc, init_stmt_after_parse(). If this flag is set
subquery becomes non-const and evaluation does not happen.
2. CREATE|ALTER VIEW, SHOW CREATE VIEW, I_S tables which
process FRM files
We use LEX::view_prepare_mode field. We set it before
view preparation and check this flag in
::fix_fields(), ::fix_length_and_dec().
Some bugs are fixed using this approach,
some are not(Bug#57352, Bug#57703). The problem here is
that we have a lot of ::fix_fields(), ::fix_length_and_dec()
where we use Item::val_...() calls for const items.
3. Derived tables with subquery = wrong result(Bug19077)
The reason of this bug is too early subquery evaluation.
It was fixed by adding Item::with_subselect field
The check of this field in appropriate places prevents
const item evaluation if the item have subquery.
The fix for Bug19077 fixes only the problem with
convert_constant_item() function and does not cover
other places(::fix_fields(), ::fix_length_and_dec() again)
where subqueries could be evaluated.
Example:
CREATE TABLE t1 (i INT, j BIGINT);
INSERT INTO t1 VALUES (1, 2), (2, 2), (3, 2);
SELECT * FROM (SELECT MIN(i) FROM t1
WHERE j = SUBSTRING('12', (SELECT * FROM (SELECT MIN(j) FROM t1) t2))) t3;
DROP TABLE t1;
4. Derived tables with subquery where subquery
is evaluated before table locking(Bug#54475, Bug#52157)
Suggested solution is following:
-Introduce new field LEX::context_analysis_only with the following
possible flags:
#define CONTEXT_ANALYSIS_ONLY_PREPARE 1
#define CONTEXT_ANALYSIS_ONLY_VIEW 2
#define CONTEXT_ANALYSIS_ONLY_DERIVED 4
-Set/clean these flags when we perform
context analysis operation
-Item_subselect::const_item() returns
result depending on LEX::context_analysis_only.
If context_analysis_only is set then we return
FALSE that means that subquery is non-const.
As all subquery types are wrapped by Item_subselect
it allow as to make subquery non-const when
it's necessary.
mysql-test/r/derived.result:
test case
mysql-test/r/multi_update.result:
test case
mysql-test/r/view.result:
test case
mysql-test/suite/innodb/r/innodb_multi_update.result:
test case
mysql-test/suite/innodb/t/innodb_multi_update.test:
test case
mysql-test/suite/innodb_plugin/r/innodb_multi_update.result:
test case
mysql-test/suite/innodb_plugin/t/innodb_multi_update.test:
test case
mysql-test/t/derived.test:
test case
mysql-test/t/multi_update.test:
test case
mysql-test/t/view.test:
test case
sql/item.cc:
--removed unnecessary code
sql/item_cmpfunc.cc:
--removed unnecessary checks
--THD::is_context_analysis_only() is replaced with LEX::is_ps_or_view_context_analysis()
sql/item_func.cc:
--refactored context analysis checks
sql/item_row.cc:
--removed unnecessary checks
sql/item_subselect.cc:
--removed unnecessary code
--added DBUG_ASSERT into Item_subselect::exec()
which asserts that subquery execution can not happen
if LEX::context_analysis_only is set, i.e. at context
analysis stage.
--Item_subselect::const_item()
Return FALSE if LEX::context_analysis_only is set.
It prevents subquery evaluation in ::fix_fields &
::fix_length_and_dec at context analysis stage.
sql/item_subselect.h:
--removed unnecessary code
sql/mysql_priv.h:
--Added new set of flags.
sql/sql_class.h:
--removed unnecessary code
sql/sql_derived.cc:
--added LEX::context_analysis_only analysis intialization/cleanup
sql/sql_lex.cc:
--init LEX::context_analysis_only field
sql/sql_lex.h:
--New LEX::context_analysis_only field
sql/sql_parse.cc:
--removed unnecessary code
sql/sql_prepare.cc:
--removed unnecessary code
--added LEX::context_analysis_only analysis intialization/cleanup
sql/sql_select.cc:
--refactored context analysis checks
sql/sql_show.cc:
--added LEX::context_analysis_only analysis intialization/cleanup
sql/sql_view.cc:
--added LEX::context_analysis_only analysis intialization/cleanup
------------------------------------------------------------
revno: 2572.2.1
revision-id: sp1r-davi@mysql.com/endora.local-20080227225948-16317
parent: sp1r-anozdrin/alik@quad.-20080226165712-10409
committer: davi@mysql.com/endora.local
timestamp: Wed 2008-02-27 19:59:48 -0300
message:
Bug#27525 table not found when using multi-table-deletes with aliases over several databas
Bug#30234 Unexpected behavior using DELETE with AS and USING
The multi-delete statement has a documented limitation that
cross-database multiple-table deletes using aliases are not
supported because it fails to find the tables by alias if it
belongs to a different database. The problem is that when
building the list of tables to delete from, if a database
name is not specified (maybe an alias) it defaults to the
name of the current selected database, making impossible to
to properly resolve tables by alias later. Another problem
is a inconsistency of the multiple table delete syntax that
permits ambiguities in a delete statement (aliases that refer
to multiple different tables or vice-versa).
The first step for a solution and proper implementation of
the cross-databse multiple table delete is to get rid of any
ambiguities in a multiple table statement. Currently, the parser
is accepting multiple table delete statements that have no obvious
meaning, such as:
DELETE a1 FROM db1.t1 AS a1, db2.t2 AS a1;
DELETE a1 AS a1 FROM db1.t1 AS a1, db2.t2 AS a1;
The solution is to resolve the left part of a delete statement
using the right part, if the a table on right has an alias,
it must be referenced in the left using the given alias. Also,
each table on the left side must match unambiguously only one
table in the right side.
mysql-test/r/delete.result:
Add test case result for Bug#27525 and Bug#21148
mysql-test/r/derived.result:
Update error.
mysql-test/suite/rpl/r/rpl_multi_delete2.result:
Update syntax.
mysql-test/suite/rpl/t/rpl_multi_delete2.test:
Update syntax.
mysql-test/t/delete.test:
Add test case for Bug#27525 and Bug#21148
mysql-test/t/derived.test:
Update statement error, alias is properly resolved now.
sql/sql_parse.cc:
Implement new algorithm for the resolution of alias in
a multiple table delete statement.
sql/sql_yacc.yy:
Rework multi-delete parser rules to not accept table alias
for the table source list.
sql/table.h:
Add flag to signal that the table has a alias set or
that fully qualified table name was given.
mutually-nested subqueries
Queries of the form
SELECT * FROM (SELECT 1) AS t1,
(SELECT 2) AS t2,...
(SELECT 32) AS t32
caused the "Too high level of nesting for select" error
as if the query has a form
SELECT * FROM (SELECT 1 FROM (SELECT 2 FROM (SELECT 3 FROM...
The table_factor parser rule has been modified to adjust
the LEX::nest_level variable value after every derived table.
mysql-test/r/derived.result:
Added test case for bug #41156.
mysql-test/t/derived.test:
Added test case for bug #41156.
sql/sql_yacc.yy:
Bug #41156: List of derived tables acts like a chain of
mutually-nested subqueries
The select_derived2 parser rule calls mysql_new_select()
calls push_context() and nest_level++, however only
the pop_context() was called at the end of derived table
parsing at the table_factor rule.
The table_factor parser rule has been modified to adjust
the LEX::nest_level variable value after every derived table.
Details:
Most tests mentioned within the bug report were already fixed.
The test modified here failed in stability (high parallel load) tests.
Details:
1. Take care that disconnects are finished before the test terminates.
2. Correct wrong handling of send/reap in events_stress which caused
random garbled output
3. Minor beautifying of script code
No warning was generated when a TIMESTAMP with a non-zero time part
was converted to a DATE value. This caused index lookup to assume
that this is a valid conversion and was returning rows that match
a comparison between a TIMESTAMP value and a DATE keypart.
Fixed by generating a warning on such a truncation.
mysql-test/r/derived.result:
Bug #31221: fixed an existing not-precise test case
mysql-test/r/ps_2myisam.result:
Bug #31221: Warnings cased by existing tests
mysql-test/r/ps_3innodb.result:
Bug #31221: Warnings cased by existing tests
mysql-test/r/ps_4heap.result:
Bug #31221: Warnings cased by existing tests
mysql-test/r/ps_5merge.result:
Bug #31221: Warnings cased by existing tests
mysql-test/r/ps_6bdb.result:
Bug #31221: Warnings cased by existing tests
mysql-test/r/ps_7ndb.result:
Bug #31221: Warnings cased by existing tests
mysql-test/r/type_date.result:
Bug #31221: Warnings cased by existing tests
mysql-test/r/type_datetime.result:
Bug #31221: test case
mysql-test/t/derived.test:
Bug #31221: fixed an existing not-precise test case
mysql-test/t/type_date.test:
Bug #31221: test case
sql/field.cc:
Bug #31221:
- Upgraded fix for bug 29729
- issue a warning only if the hh:mm:ss.msec is not zero consistently
for all the Field_newdate::store function
sql/item_timefunc.cc:
Bug #31221: don't ignore the errors when storing data
