Use SELECT_LEX to save lists for ORDER BY and GROUP BY before parsing
WINDOW clauses / specifications. This is needed for proper parsing
of a nested WINDOW clause when a WINDOW clause is used in a subquery
contained in another WINDOW clause.
Fix assignment of empty SQL_I_List to another one (in case of empty list
next shoud point on first).
it's incorrect to use change_item_tree() to replace arguments
of top-level AND/OR, because they (arguments) are stored in a List,
so a pointer to an argument is in the list_node, and individual
list_node's of top-level AND/OR can be deleted in Item_cond::build_equal_items().
In that case rollback_item_tree_changes() will modify the deleted object.
Luckily, it's not needed to use change_item_tree() for top-level
AND/OR, because the whole top-level item is copied and preserved
in prep_where and prep_on, and restored from there.
So, just don't.
Additionally to the test case in the commit it fixes
* ASAN failure of main.opt_tvc --ps
* ASAN failure of main.having_cond_pushdown --ps
The cause of regression was handling for ROWNUM() function.
For queries like
SELECT ROWNUM() FROM ... ORDER BY ...
ROWNUM() should be computed before the ORDER BY.
The computation was moved to be before the ORDER BY for any entries in
the select list that had RAND_TABLE_BIT set.
This had a negative impact on queries in form:
SELECT sp_func() FROM t1 ORDER BY ... LIMIT n
where sp_func() is NOT declared as DETERMINISTIC (and so has
RAND_TABLE_BIT set).
The fix is to require evaluation for sorting only for the ROWNUM()
function. Functions that just have RAND_TABLE_BIT() can be computed
after ORDER BY ... LIMIT is applied.
(think about a possible index that satisfies the ORDER BY clause. In
that case, the the rows would be read in the needed order and we would
stop after reading LIMIT rows, achieving the same effect).
For commands
(1) alter table t1 add partition (partition p2);
(2) alter table t1 add partition (partition px history);
It printed the same error message:
Wrong partitioning type, expected type: `SYSTEM_TIME`
For (1) it is not clear from the syntax that we are trying to add
HASH partition. For (2) it is not clear that the table partitioning is
different than SYSTEM_TIME. Now it prints what type we are trying to
add to what type of partitioning.
Fixed warning unused function rename_field_in_list() for compilation
without partitioning.
For commands
(1) alter table t1 add partition (partition p2);
(2) alter table t1 add partition (partition px history);
It printed the same error message:
Wrong partitioning type, expected type: `SYSTEM_TIME`
For (1) it is not clear from the syntax that we are trying to add
HASH partition. For (2) it is not clear that the table partitioning is
different than SYSTEM_TIME. Now it prints what type we are trying to
add to what type of partitioning.
To prevent ASAN heap-use-after-poison in the MDEV-16549 part of
./mtr --repeat=6 main.derived
the initialization of Name_resolution_context was cleaned up.
st_select_lex::init_query is called in the exectuion of EXECUTE
IMMEDIATE 'alter table ...'. so reset the initialization at the
same point we set join= 0.
Underlying causes of all bugs mentioned below are same. This patch fixes
all of them:
1) MDEV-25028: ASAN use-after-poison in
base_list_iterator::next or Assertion `sl->join == 0' upon
INSERT .. RETURNING via PS
2) MDEV-25187: Assertion `inited == NONE || table->open_by_handler'
failed or Direct leak in init_dynamic_array2 upon INSERT .. RETURNING
and memory leak in init_dynamic_array2
3) MDEV-28740: crash in INSERT RETURNING subquery in prepared statements
4) MDEV-27165: crash in base_list_iterator::next
5) MDEV-29686: Assertion `slave == 0' failed in
st_select_lex_node::attach_single
Analysis:
consider this statement:
INSERT(1)...SELECT(2)...(SELECT(3)...) RETURNING (SELECT(4)...)
When RETURNING is encountered, add_slave() changes how selects are linked.
It makes the builtin_select(1) slave of SELECT(2). This causes
losing of already existing slave(3) (which is nested select of SELECT of
INSERT...SELECT). When really, builtin_select (1) shouldn't be slave to
SELECT(2) because it is not nested within it. Also, push_select() to use
correct context also changed how select are linked.
During reinit_stmt_before_use(), we expect the selects to
be cleaned-up and have join=0. Since these selects are not linked correctly,
clean-up doesn't happen correctly so join is not NULL. Hence the crash.
Fix:
IF we are parsing RETURNING, make is_parsing_returning= true for
current select. get rid of add_slave(). In place of push_select(), used
push_context() to have correct context (the context of builtin_select)
to resolve items in item_list. And add these items to item_list of
builtin_select.
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.
