Problem: Item_param::basic_const_item() returned true when fixed==false.
This unexpected combination made Item::const_charset_converter() crash
on asserts.
Fix:
- Changing all Item_param::set_xxx() to set "fixed" to true.
This fixes the problem.
- Additionally, changing all Item_param::set_xxx() to set
Item_param::item_type, to avoid duplicate code, and for consistency,
to make the code symmetric between different constant types.
Before this patch only set_null() set item_type.
- Moving Item_param::state and Item_param::item_type from public to private,
to make sure easier that these members are in sync with "fixed" and to
each other.
- Adding a new argument "unsigned_arg" to Item::set_decimal(),
and reusing it in two places instead of duplicate code.
- Adding a new method Item_param::fix_temporal() and reusing it in two places.
- Adding methods has_no_value(), has_long_data_value(), has_int_value(),
instead of direct access to Item_param::state.
check_that_all_fields_are_given_values() relied on write_set,
but was run too early, before triggers updated write_set.
also, when triggers are present, fields might get values conditionally,
so we need to check that all fields are given values for every row.
This patch adds DEFAULT as a possible dynamic SQL parameter, e.g.:
EXECUTE IMMEDIATE 'INSERT INTO t1 (column) VALUES(?)' USING DEFAULT;
EXECUTE IMMEDIATE 'UPDATE t1 SET column=?' USING DEFAULT;
and for similar PREPARE..EXECUTE queries.
This is done for symmetry with the STMT_INDICATOR_DEFAULT indicator in
the client-server PS protocol.
The changes include:
- Allowing DEFAULT as a possible option in execute USING clause (sql_yacc.yy)
- Adding "virtual bool Item::save_in_param(THD *thd, Item_param *param)",
because "normal" items (that have real values) and Item_default_value
have now different actions when assigning itself as an Item_param value.
- Fixing switch() statements in a few Item_param methods not to have "default",
because it was easy to forget to add a new "case" when adding a new XXX_VALUE
value into the enum Item_param::enum_item_param_state.
This is important, as we'll be adding new values soon, e.g. for MDEV-11359.
Removing "default" helped to find and report bugs MDEV-11361 and MDEV-11362,
because DECIMAL_VALUE is obviously not properly handled in some cases.
The server missed to call check_dependencies_in_with_clauses()
when processing PREPARE ... FROM CREATE ... SELECT / INSERT ... SELECT
with WITH clause before SELECT.
mysqld maintains a list of TABLE objects for all temporary
tables created within a session in THD. Here each table is
represented by a TABLE object.
A query referencing a particular temporary table for more
than once, however, failed with ER_CANT_REOPEN_TABLE error
because a TABLE_SHARE was allocate together with the TABLE,
so temporary tables always had only one TABLE per TABLE_SHARE.
This patch lift this restriction by separating TABLE and
TABLE_SHARE objects and storing TABLE_SHAREs for temporary
tables in a list in THD, and TABLEs in a list within their
respective TABLE_SHAREs.
"Re-factor the code for post-join operations".
The patch mainly contains the code ported from mysql-5.6 and
created for two essential architectural changes:
1. WL#5558: Resolve ORDER BY execution method at the optimization stage
2. WL#6071: Inline tmp tables into the nested loops algorithm
The first task was implemented for mysql-5.6 by Ole John Aske.
It allows to make all decisions on ORDER BY operation at the optimization
stage.
The second task implemented for mysql-5.6 by Evgeny Potemkin adds JOIN_TAB
nodes for post-join operations that require temporary tables. It allows
to execute these operations within the nested loops algorithm that used to
be used before this task only for join queries. Besides these task moves
all planning on the execution of these operations from the execution phase
to the optimization phase.
Some other re-factoring changes of mysql-5.6 were pulled in, mainly because
it was easier to pull them in than roll them back. In particular all
changes concerning Ref_ptr_array were incorporated.
The port required some changes in the MariaDB code that concerned the
functionality of EXPLAIN and ANALYZE. This was done mainly by Sergey
Petrunia.
MDEV-8938 Server Crash on Update with joins
Make unique table check after setup_fields of update because unique table can materialize table and we do not need field resolving after materialization.
Make unique table check after setup_fields of update because unique table can materialize table and we do not need field resolving after materialization.
Issue:
======
While re-preparing the statement in
Prepared_statement::swap_prepared_statement for swapping
the database of PS we only swapped the db string but not
its length. This resulted in mismatch between the actual
string and its length. In one particular case where db
of PS was dropped, we have db as null pointer and length
as non-zero. strdup which used above values resulted in
invalid memory access.
Solution:
=========
In Prepared_statement::swap_prepared_statement also swap
db_length along with db variable. Also, remove
DBUG_ASSERT(db_length == copy->db_length) as this have
no meaning if they are 2 different entities.
When CHANGE MASTER was executed as a PS, its attributes were wrongly
getting reset toward the end of PREPARE. As a result, the subsequent
executions had no effect. Fixed by making sure that the CHANGE MASTER
attributes are preserved during the lifetime of the PS.
