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4047 commits

Author SHA1 Message Date
Jan Lindström
f57deb314f MDEV-31660 : Assertion `client_state.transaction().active() in wsrep_append_key
At the moment we cannot support
wsrep_forced_binlog_format=[MIXED|STATEMENT]
during CREATE TABLE AS SELECT.
Statement will use ROW instead and give
a warning.

Signed-off-by: Julius Goryavsky <julius.goryavsky@mariadb.com>
2023-09-29 12:54:04 +02:00
Dmitry Shulga
be02356206 MDEV-14959: Fixed memory leak happened on re-parsing a view that substitutes a table
In case a table accessed by a PS/SP is dropped after the first execution of
PS/SP and a view created with the same name as a table just dropped then
the second execution of PS/SP leads to allocation of a memory on SP/PS
memory root already marked as read only on first execution.

For example, the following test case:
CREATE TABLE t1 (a INT);
PREPARE stmt FROM "INSERT INTO t1 VALUES (1)";
EXECUTE stmt;
DROP TABLE t1;
CREATE VIEW t1 S SELECT 1;
--error ER_NON_INSERTABLE_TABLE
EXECUTE stmt; # (*)
DROP VIEW t1;

will hit assert on running the statement 'EXECUTE stmt' marked with (*)
when allocation of a memory be performed on parsing the view.

Memory allocation is requested inside the function mysql_make_view
when a view definition being parsed. In order to avoid an assertion
failure, call of the function mysql_make_view() must be moved after
invocation of the function check_and_update_table_version().
It will result in re-preparing the whole PS statement or current
SP instruction that will free currently allocated items and reset
read_only flag for the memory root.
2023-09-02 13:00:00 +07:00
Dmitry Shulga
1d502a29e5 MDEV-14959: Fixed possible memory leaks that could happen on running PS/SP depending on a trigger
Moved call of the function check_and_update_table_version() just
before the place where the function extend_table_list() is invoked
in order to avoid allocation of memory on a PS/SP memory root
marked as read only. It happens by the reason that the function
extend_table_list() invokes sp_add_used_routine() to add a trigger
created for the table in time frame between execution the statement
EXECUTE `stmt_id` .

For example, the following test case
create table t1 (a int);

prepare stmt from "insert into t1 (a) value (1)";
execute stmt;

create trigger t1_bi before insert on t1 for each row
  set @message= new.a;

execute stmt; # (*)

adds the trigger t1_bi to a list of used routines that involves
allocation of a memory on PS memory root that has been already marked
as read only on first run of the statement 'execute stmt'.
In result, when the statement marked with (*) is executed it results in
assert hit.

To fix the issue call the function check_and_update_table_version()
before invocation of extend_table_list() to force re-compilation of
PS/SP that resets read-only flag of its memory root.
2023-09-02 13:00:00 +07:00
Aleksey Midenkov
3e7561cf35 MDEV-29357 Assertion (fixed) in Item_func_dayname on INSERT
Restrict vcol_cleanup_expr() in close_thread_tables() to only simple
locked tables mode. Prelocked is cleaned up like normal statement: in
close_thread_table().
2023-07-20 18:22:31 +03:00
Igor Babaev
ccec9b1de9 MDEV-30706 Different results of selects from view and CTE with same definition
MDEV-30668 Set function aggregated in outer select used in view definition

This patch fixes two bugs concerning views whose specifications contain
subqueries with set functions aggregated in outer selects.
Due to the first bug those such views that have implicit grouping were
considered as mergeable. This led to wrong result sets for selects from
these views.
Due to the second bug the aggregation select was determined incorrectly and
this led to bogus error messages.
The patch added several test cases for these two bugs and for four other
duplicate bugs.
The patch also enables view-protocol for many other test cases.

Approved by Oleksandr Byelkin <sanja@mariadb.com>
2023-03-02 07:51:33 -08:00
Oleksandr Byelkin
a6a906d766 MDEV-26831 fallout: fix problems of name resolution cache
- Avoid passing real field cache as a parameter when we check for duplicates.

- Correct cache cleanup (cached field number also have to be reset).

- Name resolution cache simple test added.
2023-03-02 09:24:54 +01:00
Vicențiu Ciorbaru
08c852026d Apply clang-tidy to remove empty constructors / destructors
This patch is the result of running
run-clang-tidy -fix -header-filter=.* -checks='-*,modernize-use-equals-default' .

Code style changes have been done on top. The result of this change
leads to the following improvements:

1. Binary size reduction.
* For a -DBUILD_CONFIG=mysql_release build, the binary size is reduced by
  ~400kb.
* A raw -DCMAKE_BUILD_TYPE=Release reduces the binary size by ~1.4kb.

2. Compiler can better understand the intent of the code, thus it leads
   to more optimization possibilities. Additionally it enabled detecting
   unused variables that had an empty default constructor but not marked
   so explicitly.

   Particular change required following this patch in sql/opt_range.cc

   result_keys, an unused template class Bitmap now correctly issues
   unused variable warnings.

   Setting Bitmap template class constructor to default allows the compiler
   to identify that there are no side-effects when instantiating the class.
   Previously the compiler could not issue the warning as it assumed Bitmap
   class (being a template) would not be performing a NO-OP for its default
   constructor. This prevented the "unused variable warning".
2023-02-09 16:09:08 +02:00
Sergei Golubchik
d4f6d2f08f Merge branch '10.3' into 10.4 2022-10-01 23:07:26 +02:00
Oleksandr Byelkin
f65ba9aeb7 MDEV-17124: mariadb 10.1.34, views and prepared statements: ERROR 1615 (HY000): Prepared statement needs to be re-prepared
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.
2022-09-30 12:11:37 +02:00
Anel Husakovic
1f51d6c0f6 MDEV-28548: ER_TABLEACCESS_DENIED_ERROR is missing information about DB
- Added missing information about database of corresponding table for various types of commands
- Update some typos

- Reviewed by: <vicentiu@mariadb.org>
2022-09-30 08:48:57 +02:00
Oleksandr Byelkin
3bb36e9495 Merge branch '10.3' into 10.4 2022-07-27 11:02:57 +02:00
Oleg Smirnov
49e14000ee MDEV-26427 MariaDB Server SEGV on INSERT .. SELECT
1. For INSERT..SELECT statements: don't include table/view the data
   is inserted into in the list of leaf tables
2. Remove duplicated and dead code related to table_count
2022-07-14 11:07:24 +07:00
Sergei Golubchik
a70a1cf3f4 Merge branch '10.3' into 10.4 2022-05-08 23:03:08 +02:00
Sergei Golubchik
0beed9b5e9 MDEV-28097 use-after-free when WHERE has subquery with an outer reference in HAVING
when resolving WHERE and ON clauses, do not look in
SELECT list/aliases.
2022-04-29 17:05:19 +02:00
Sergei Golubchik
bc9102eb81 cleanup: (*order->item) -> item
and minor style fixes
2022-04-29 17:05:12 +02:00
Aleksey Midenkov
182b8a29e7 MDEV-20077 compilation fix 2022-04-29 17:36:48 +03:00
Aleksey Midenkov
ddc416c606 MDEV-20077 Warning on full history partition is delayed until next DML statement
Moved LIMIT warning from vers_set_hist_part() to new call
vers_check_limit() at table unlock phase. At that point
read_partitions bitmap is already pruned by DML code (see
prune_partitions(), find_used_partitions()) so we have to set
corresponding bits for working history partition.

Also we don't do my_error(ME_WARNING|ME_ERROR_LOG), because at that
point it doesn't update warnings number, so command reports 0 warnings
(but warning list is still updated). Instead we do
push_warning_printf() and sql_print_warning() separately.

Under LOCK TABLES external_lock(F_UNLCK) is not executed. There is
start_stmt(), but no corresponding "stop_stmt()". So for that mode we
call vers_check_limit() directly from close_thread_tables().

Test result has been changed according to new LIMIT and warning
printing algorithm. For convenience all LIMIT warnings are marked with
"You see warning above ^".

TODO MDEV-20345 fixed. Now vers_history_generating() contains
fine-grained list of DML-commands that can generate history (and TODO
mechanism worked well).
2022-04-29 13:31:42 +03:00
Marko Mäkelä
394784095e Merge 10.3 into 10.4 2022-04-21 11:33:59 +03:00
Marko Mäkelä
b3c3291f0b MDEV-24176 fixup: GCC -Wmaybe-uninitialized 2022-04-19 10:29:21 +03:00
Aleksey Midenkov
08c7ab404f MDEV-24176 Server crashes after insert in the table with virtual
column generated using date_format() and if()

vcol_info->expr is allocated on expr_arena at parsing stage. Since
expr item is allocated on expr_arena all its containee items must be
allocated on expr_arena too. Otherwise fix_session_expr() will
encounter prematurely freed item.

When table is reopened from cache vcol_info contains stale
expression. We refresh expression via TABLE::vcol_fix_exprs() but
first we must prepare a proper context (Vcol_expr_context) which meets
some requirements:

1. As noted above expr update must be done on expr_arena as there may
be new items created. It was a bug in fix_session_expr_for_read() and
was just not reproduced because of no second refix. Now refix is done
for more cases so it does reproduce. Tests affected: vcol.binlog

2. Also name resolution context must be narrowed to the single table.
Tested by: vcol.update main.default vcol.vcol_syntax gcol.gcol_bugfixes

3. sql_mode must be clean and not fail expr update.

sql_mode such as MODE_NO_BACKSLASH_ESCAPES, MODE_NO_ZERO_IN_DATE, etc
must not affect vcol expression update. If the table was created
successfully any further evaluation must not fail. Tests affected:
main.func_like

Reviewed by: Sergei Golubchik <serg@mariadb.org>
2022-04-18 12:44:27 +03:00
Aleksey Midenkov
c02ebf3510 MDEV-24176 Preparations
1. moved fix_vcol_exprs() call to open_table()

mysql_alter_table() doesn't do lock_tables() so it cannot win from
fix_vcol_exprs() from there. Tests affected: main.default_session

2. Vanilla cleanups and comments.
2022-04-18 12:44:27 +03:00
Sergei Golubchik
b4477ae73c Merge branch '10.3' into 10.4 2022-02-10 20:39:13 +01:00
Sergei Golubchik
a36fc80aeb Merge branch '10.2' into 10.3 2022-02-10 20:23:56 +01:00
Oleksandr Byelkin
0168d1eda3 MDEV-25766 Unused CTE lead to a crash in find_field_in_tables/find_order_in_list
Do not assume that subquery Item always present.
2022-02-10 14:36:25 +01:00
Oleksandr Byelkin
a576a1cea5 Merge branch '10.3' into 10.4 2022-01-30 09:46:52 +01:00
Oleksandr Byelkin
41a163ac5c Merge branch '10.2' into 10.3 2022-01-29 15:41:05 +01:00
Jan Lindström
a38b937bf1 MDEV-25201 : Assertion `thd->wsrep_trx_meta.gtid.seqno == (-1)' failed in int wsrep_to_isolation_begin(THD*, const char*, const char*, const TABLE_LIST*, Alter_info*)
Test case does not assert anymore but works incorrectly. We should
not replicate PREPARE using TOI.
2022-01-11 09:43:59 +02:00
Dmitry Shulga
89c870b2b4 MDEV-20325: Assertion outer_context || !*from_field || *from_field == not_found_field' failed in Item_field::fix_outer_field | !derived->is_excluded()' failed in TABLE_LIST::set_check_materialized | SIGEGV in st_select_lex::mark_as_dependent (optimized builds)
Re-execution of a query containing subquery in the FROM clause results
in assert failure in case the query is run as part of a stored routine or
as a prepared statement AND derived table merge optimization is off.
As an example, the following test case
  CREATE TABLE t1 (a INT) ;
  CREATE PROCEDURE sp() SELECT * FROM (SELECT a FROM t1) tb;
  CALL sp();
  SET optimizer_switch='derived_merge=off';
  CALL sp();
results in assert failure on the second invocation of the 'sp' stored routine.

The reason for assertion failure is that the expression
  derived->is_excluded()
returns the value true where the value false expected.

The method is_excluded() returns the value true for a derived table
that has been merged to a parent select. Such transformation happens as part
of Derived Table Merge Optimization that is performed on first invocation of
a stored routine or a prepared statement containing a query with subquery
in the FROM clause of the main SELECT.

When the same routine or prepared statement is run the second time and
Derived Table Merge Optimization is OFF the MariaDB server tries to materialize
a derived table specified by the subquery that fails since this subquery
has already been merged to the top-most SELECT. This transformation is permanent
and can't be reverted. That is the reason why the assert
  DBUG_ASSERT(!derived->is_excluded());
fails inside the function TABLE_LIST::set_check_materialized().

Similar behaviour can be observed in case a stored routine or prepared statement
containing a SELECT statement with subquery in the FROM clause, first is run
with the optimizer_switch option set to derived_merge=off and re-run after this
option has been switched to derived_merge=on. In this case a derived table for
subquery is materialized on the first execution and marked as merged derived
table on the second execution that results in error with misleading error
message:

MariaDB [test]> CALL sp1();
ERROR 1030 (HY000): Got error 1 "Operation not permitted" from storage engine MEMORY

To fix the issue, a derived table that has been already optimized shouldn't be
re-marked for one more round of optimization.

One significant consequence following from suggested change is that the data
member TABLE_LIST::derived_type is not updated once the table optimization
has been done. This fact should be taken into account when Prepared Statement
being handled since once a table listed in a query has been optimized on
execution of the statement PREPARE FROM it won't be touched anymore on handling
the statement EXECUTE.

One side effect caused by this change could be observed for the following
test case:
  CREATE TABLE t1 (s1 INT);
  CREATE VIEW v1 AS
    SELECT s1,s2 FROM (SELECT s1 as s2 FROM t1 WHERE s1 <100) x, t1 WHERE t1.s1=x.s2;
  INSERT INTO v1 (s1) VALUES (-300);

  PREPARE stmt FROM "INSERT INTO v1 (s1) VALUES (-300)";
  EXECUTE stmt;

Execution of the above EXECUTE statement results in issuing the error
ER_COLUMNACCESS_DENIED_ERROR since table_ref->is_merged_derived() is false
and check_column_grant_in_table_ref() called for a temporary table that
shouldn't be. To fix this issue the function find_field_in_tables has been
modified in such a way that the function check_column_grant_in_table_ref()
is not called for a temporary table.
2022-01-11 11:50:29 +07:00
Igor Babaev
d6ee351bbb Revert "MDEV-24454 Crash at change_item_tree"
This patch reverts the fixes of the bugs MDEV-24454 and MDEV-25631 from
the commit 3690c549c6.
It leaves the changes in plugin/feedback/feedback.cc and corresponding
test files introduced in this commit intact.

Proper fixes for the bug MDEV-24454 and MDEV-25631 will follow immediately.
2022-01-10 09:12:17 -08:00
Marko Mäkelä
a736a3174a Merge 10.3 into 10.4 2021-10-13 12:03:32 +03:00
Aleksey Midenkov
1e70b287e7 MDEV-25891 Computed default for INVISIBLE column is ignored in INSERT
There are two fill_record() functions (lines 8343 and 8618). First one
is used when there are some explicit values, the second one is used
for all implicit values. First one does update_default_fields(), the
second one did not. Added update_default_fields() call to the implicit
version of fill_record().
2021-10-11 13:36:07 +03:00
Marko Mäkelä
a10b63bf58 Merge 10.3 into 10.4 2021-09-29 16:03:02 +03:00
Marko Mäkelä
742b37a345 Merge 10.2 into 10.3 2021-09-29 15:04:20 +03:00
Oleksandr Byelkin
3690c549c6 MDEV-24454 Crash at change_item_tree
Use in_sum_func (and so nest_level) only in LEX to which SELECT lex belong to

Reduce usage of current_select (because it does not always point on the correct
 SELECT_LEX, for example with prepare.

Change context for all classes inherited from Item_ident (was only for Item_field) in case of pushing down it to HAVING.

Now name resolution context have to have SELECT_LEX reference if the context is present.

Fixed feedback plugin stack usage.
2021-09-27 11:00:51 +02:00
Vicențiu Ciorbaru
de7e027d5e Merge remote-tracking branch 'upstream/10.3' into 10.4 2021-09-09 09:23:35 +03:00
Oleksandr Byelkin
391f6b4f1e MDEV-26362: incorrect nest_level value with INTERSECT
Add DBUG_ASSERT (should be kept in merge)
Fix nest_level assignment in LEX::add_unit_in_brackets (should be ignored in merge to 10.4)
2021-09-05 10:38:12 +02:00
Marko Mäkelä
0464761126 Merge 10.3 into 10.4 2021-08-31 09:22:21 +03:00
Michael Widenius
b378ddb3d3 MDEV 22785 Crash with prepared statements and NEXTVAL()
The problem was that a PREARE followed by a non prepared statement
using DEFAULT NEXT_VALUE() could change table->next_local to point to
a not persitent memory aria. The next EXECUTE would then try to use
the wrong pointer, which could cause a crash.
Fixed by reseting the pointer to it's old value when doing EXECUTE.
2021-08-26 07:07:46 +03:00
Oleksandr Byelkin
7841a7eb09 Merge branch '10.3' into 10.4 2021-07-31 22:59:58 +02:00
Sergei Golubchik
6190a02f35 Merge branch '10.2' into 10.3 2021-07-21 20:11:07 +02:00
Nikita Malyavin
c47e4aab62 MDEV-23597 Assertion `marked_for_read()' failed while evaluating DEFAULT
The columns that are part of DEFAULT expression were not read-marked
in statements like UPDATE...SET b=DEFAULT.

The problem is `F(DEFAULT)` expression depends of the left-hand side of an
assignment. However, setup_fields accepts only right-hand side value.
Neither Item::fix_fields does.

Suchwise, b=DEFAULT(b) works fine, because Item_default_field has
information on what field it is default of:
    if (thd->mark_used_columns != MARK_COLUMNS_NONE)
      def_field->default_value->expr->update_used_tables();

in Item_default_value::fix_fields().

It is not reasonable to pass a left-hand side to Item:fix_fields, because
the case is rare, so the rewrite
  b= F(DEFAULT)  ->  b= F(DEFAULT(b))

is made instead.

Both UPDATE and multi-UPDATE are affected, however any form of INSERT
is not: it marks all the fields in DEFAULT expressions for read in
TABLE::mark_default_fields_for_write().
2021-07-16 13:31:19 +03:00
Nikita Malyavin
7d9ba57da4 [1/2] MDEV-18166 ASSERT_COLUMN_MARKED_FOR_READ failed on tables with vcols
This is a 10.2+ part of a jira task

The two bugs regarding virtual column marking have been fixed:

1. UPDATE of a partitioned table, where the optimizer has chosen a
 secondary index to make a filesort;
2. INSERT into a table with a nonblob field generated from a blob, with
 binlog enabled and binlog_row_image=noblob.

3. DELETE from a view on a table with virtual column.

Generally the assertion happens from update_virtual_fields() call

These bugs are root-caused by missing field marking for dependant fields
of a virtual column.

Therefore a fix is: mark all the fields involved in the vcol expression by
calling field->register_field_in_read_map() instead just setting a single
bit.

3 was reproducible only on 10.4+, however the problem might has just been
invisible in the earlier versions. The fix is applicable to 10.2-10.3 as
well.
2021-07-12 22:00:39 +03:00
Marko Mäkelä
77d8da57d7 Merge 10.3 into 10.4 2021-06-01 09:14:59 +03:00
Marko Mäkelä
950a220060 Merge 10.2 into 10.3 2021-06-01 08:40:59 +03:00
Dmitry Shulga
91bde0fb67 MDEV-25576: The statement EXPLAIN running as regular statement and as prepared statement produces different results for UPDATE with subquery
Both EXPLAIN and EXPLAIN EXTENDED statements produce different results set
in case it is run in normal way and in PS mode for the statements
UPDATE/DELETE with subquery.

The use case below reproduces the issue:
MariaDB [test]> CREATE TABLE t1 (c1 INT KEY) ENGINE=MyISAM;
Query OK, 0 rows affected (0,128 sec)

MariaDB [test]> CREATE TABLE t2 (c2 INT) ENGINE=MyISAM;
Query OK, 0 rows affected (0,023 sec)

MariaDB [test]> CREATE TABLE t3 (c3 INT) ENGINE=MyISAM;
Query OK, 0 rows affected (0,021 sec)

MariaDB [test]> EXPLAIN EXTENDED UPDATE t3 SET c3 =
    -> ( SELECT COUNT(d1.c1) FROM ( SELECT a11.c1 FROM t1 AS a11
    -> STRAIGHT_JOIN t2 AS a21 ON a21.c2 = a11.c1 JOIN t1 AS a12
    -> ON a12.c1 = a11.c1 ) d1 );
+------+-------------+-------+------+---------------+------+---------+------+------+----------+--------------------------------+
| id   | select_type | table | type | possible_keys | key  | key_len | ref  | rows | filtered | Extra                          |
+------+-------------+-------+------+---------------+------+---------+------+------+----------+--------------------------------+
|    1 | PRIMARY     | t3    | ALL  | NULL          | NULL | NULL    | NULL |    0 |   100.00 |                                |
|    2 | SUBQUERY    | NULL  | NULL | NULL          | NULL | NULL    | NULL | NULL |     NULL | Impossible WHERE noticed after reading const tables
+------+-------------+-------+------+---------------+------+---------+------+------+----------+--------------------------------+
2 rows in set (0,002 sec)

MariaDB [test]> PREPARE stmt FROM
    -> EXPLAIN EXTENDED UPDATE t3 SET c3 =
    -> ( SELECT COUNT(d1.c1) FROM ( SELECT a11.c1 FROM t1 AS a11
    -> STRAIGHT_JOIN t2 AS a21 ON a21.c2 = a11.c1 JOIN t1 AS a12
    -> ON a12.c1 = a11.c1 ) d1 );
Query OK, 0 rows affected (0,000 sec)
Statement prepared

MariaDB [test]>  EXECUTE stmt;
+------+-------------+-------+------+---------------+------+---------+------+------+----------+--------------------------------+
| id   | select_type | table | type | possible_keys | key  | key_len | ref  | rows | filtered | Extra                          |
+------+-------------+-------+------+---------------+------+---------+------+------+----------+--------------------------------+
|    1 | PRIMARY     | t3    | ALL  | NULL          | NULL | NULL    | NULL |    0 |   100.00 |                                |
|    2 | SUBQUERY    | NULL  | NULL | NULL          | NULL | NULL    | NULL | NULL |     NULL | no matching row in const table |
+------+-------------+-------+------+---------------+------+---------+------+------+----------+--------------------------------+
2 rows in set (0,000 sec)

The reason by that different result sets are produced is that on execution
of the statement 'EXECUTE stmt' the flag SELECT_DESCRIBE not set
in the data member SELECT_LEX::options for instances of SELECT_LEX that
correspond to subqueries used in the UPDTAE/DELETE statements.

Initially, these flags were set on parsing the statement
  PREPARE stmt FROM "EXPLAIN EXTENDED UPDATE t3 SET ..."
but latter they were reset before starting real execution of
the parsed query during handling the statement 'EXECUTE stmt';

So, to fix the issue the functions mysql_update()/mysql_delete()
have been modified to set the flag SELECT_DESCRIBE forcibly
in the data member SELECT_LEX::options for the primary SELECT_LEX
of the UPDATE/DELETE statement.
2021-05-30 17:31:55 +07:00
Monty
aa284e0237 MDEV-17749 Kill during LOCK TABLE ; ALTER TABLE causes assert
The problem was that when LOCK TABLES where unwinded as part of
a killed connection, unlink_all_closed_tables() did not like that
there was uncommited transactions.
Fixed by doing a rollback of any open transaction in this particular case.
2021-05-26 14:35:23 +03:00
Igor Babaev
04de651725 MDEV-23886 Reusing CTE inside a function fails with table doesn't exist
In the code existed just before this patch binding of a table reference to
the specification of the corresponding CTE happens in the function
open_and_process_table(). If the table reference is not the first in the
query the specification is cloned in the same way as the specification of
a view is cloned for any reference of the view. This works fine for
standalone queries, but does not work for stored procedures / functions
for the following reason.
When the first call of a stored procedure/ function SP is processed the
body of SP is parsed. When a query of SP is parsed the info on each
encountered table reference is put into a TABLE_LIST object linked into
a global chain associated with the query. When parsing of the query is
finished the basic info on the table references from this chain except
table references to derived tables and information schema tables is put
in one hash table associated with SP. When parsing of the body of SP is
finished this hash table is used to construct TABLE_LIST objects for all
table references mentioned in SP and link them into the list of such
objects passed to a pre-locking process that calls open_and_process_table()
for each table from the list.
When a TABLE_LIST for a view is encountered the view is opened and its
specification is parsed. For any table reference occurred in
the specification a new TABLE_LIST object is created to be included into
the list for pre-locking. After all objects in the pre-locking have been
looked through the tables mentioned in the list are locked. Note that the
objects referenced CTEs are just skipped here as it is impossible to
resolve these references without any info on the context where they occur.
Now the statements from the body of SP are executed one by one that.
At the very beginning of the execution of a query the tables used in the
query are opened and open_and_process_table() now is called for each table
reference mentioned in the list of TABLE_LIST objects associated with the
query that was built when the query was parsed.
For each table reference first the reference is checked against CTEs
definitions in whose scope it occurred. If such definition is found the
reference is considered resolved and if this is not the first reference
to the found CTE the the specification of the CTE is re-parsed and the
result of the parsing is added to the parsing tree of the query as a
sub-tree. If this sub-tree contains table references to other tables they
are added to the list of TABLE_LIST objects associated with the query in
order the referenced tables to be opened. When the procedure that opens
the tables comes to the TABLE_LIST object created for a non-first
reference to a CTE it discovers that the referenced table instance is not
locked and reports an error.
Thus processing non-first table references to a CTE similar to how
references to view are processed does not work for queries used in stored
procedures / functions. And the main problem is that the current
pre-locking mechanism employed for stored procedures / functions does not
allow to save the context in which a CTE reference occur. It's not trivial
to save the info about the context where a CTE reference occurs while the
resolution of the table reference cannot be done without this context and
consequentially the specification for the table reference cannot be
determined.

This patch solves the above problem by moving resolution of all CTE
references at the parsing stage. More exactly references to CTEs occurred in
a query are resolved right after parsing of the query has finished. After
resolution any CTE reference it is marked as a reference to to derived
table. So it is excluded from the hash table created for pre-locking used
base tables and view when the first call of a stored procedure / function
is processed.
This solution required recursive calls of the parser. The function
THD::sql_parser() has been added specifically for recursive invocations of
the parser.
2021-05-25 00:43:03 -07:00
Marko Mäkelä
1864a8ea93 Merge 10.2 into 10.3 2021-05-24 09:38:49 +03:00
Igor Babaev
43c9fcefc0 MDEV-23886 Reusing CTE inside a function fails with table doesn't exist
In the code existed just before this patch binding of a table reference to
the specification of the corresponding CTE happens in the function
open_and_process_table(). If the table reference is not the first in the
query the specification is cloned in the same way as the specification of
a view is cloned for any reference of the view. This works fine for
standalone queries, but does not work for stored procedures / functions
for the following reason.
When the first call of a stored procedure/ function SP is processed the
body of SP is parsed. When a query of SP is parsed the info on each
encountered table reference is put into a TABLE_LIST object linked into
a global chain associated with the query. When parsing of the query is
finished the basic info on the table references from this chain except
table references to derived tables and information schema tables is put
in one hash table associated with SP. When parsing of the body of SP is
finished this hash table is used to construct TABLE_LIST objects for all
table references mentioned in SP and link them into the list of such
objects passed to a pre-locking process that calls open_and_process_table()
for each table from the list.
When a TABLE_LIST for a view is encountered the view is opened and its
specification is parsed. For any table reference occurred in
the specification a new TABLE_LIST object is created to be included into
the list for pre-locking. After all objects in the pre-locking have been
looked through the tables mentioned in the list are locked. Note that the
objects referenced CTEs are just skipped here as it is impossible to
resolve these references without any info on the context where they occur.
Now the statements from the body of SP are executed one by one that.
At the very beginning of the execution of a query the tables used in the
query are opened and open_and_process_table() now is called for each table
reference mentioned in the list of TABLE_LIST objects associated with the
query that was built when the query was parsed.
For each table reference first the reference is checked against CTEs
definitions in whose scope it occurred. If such definition is found the
reference is considered resolved and if this is not the first reference
to the found CTE the the specification of the CTE is re-parsed and the
result of the parsing is added to the parsing tree of the query as a
sub-tree. If this sub-tree contains table references to other tables they
are added to the list of TABLE_LIST objects associated with the query in
order the referenced tables to be opened. When the procedure that opens
the tables comes to the TABLE_LIST object created for a non-first
reference to a CTE it discovers that the referenced table instance is not
locked and reports an error.
Thus processing non-first table references to a CTE similar to how
references to view are processed does not work for queries used in stored
procedures / functions. And the main problem is that the current
pre-locking mechanism employed for stored procedures / functions does not
allow to save the context in which a CTE reference occur. It's not trivial
to save the info about the context where a CTE reference occurs while the
resolution of the table reference cannot be done without this context and
consequentially the specification for the table reference cannot be
determined.

This patch solves the above problem by moving resolution of all CTE
references at the parsing stage. More exactly references to CTEs occurred in
a query are resolved right after parsing of the query has finished. After
resolution any CTE reference it is marked as a reference to to derived
table. So it is excluded from the hash table created for pre-locking used
base tables and view when the first call of a stored procedure / function
is processed.
This solution required recursive calls of the parser. The function
THD::sql_parser() has been added specifically for recursive invocations of
the parser.
2021-05-21 16:00:35 -07:00
Marko Mäkelä
8c73fab7f7 Merge 10.3 into 10.4 2021-05-10 09:52:01 +03:00