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3666 Commits

Author SHA1 Message Date
098c0f2634 Merge 10.4 into 10.5 2022-07-27 17:17:24 +03:00
3bb36e9495 Merge branch '10.3' into 10.4 2022-07-27 11:02:57 +02:00
7b0e68b8a2 fix DBUG_ENTER awake_no_mutex 2022-07-22 14:59:18 +02:00
ef781162ff Merge branch '10.4' into 10.5 2022-05-09 22:04:06 +02:00
a70a1cf3f4 Merge branch '10.3' into 10.4 2022-05-08 23:03:08 +02:00
6f741eb6e4 Merge branch '10.2' into 10.3 2022-05-07 11:48:15 +02:00
a5dc12eefd MDEV-28310 Missing binlog data for INSERT .. ON DUPLICATE KEY UPDATE
MDEV-21810 MBR: Unexpected "Unsafe statement" warning for unsafe IODKU

MDEV-17614 fixes to replication unsafety for INSERT ON DUP KEY UPDATE
on two or more unique key table left a flaw. The fixes checked the
safety condition per each inserted record with the idea to catch a user-created
value to an autoincrement column and when that succeeds the autoincrement column
would become the source of unsafety too.
It was not expected that after a duplicate error the next record's
write_set may become different and the unsafe decision for that
specific record will be computed to screw the Query's binlogging
state and when @@binlog_format is MIXED nothing gets bin-logged.

This case has been already fixed in 10.5.2 by 91ab42a823 that
relocated/optimized THD::decide_logging_format_low() out of the record insert
loop. The safety decision is computed once and at the right time.
Pertinent parts of the commit are cherry-picked.

Also a spurious warning about unsafety is removed when MIXED
@@binlog_format; original MDEV-17614 test result corrected.
The original test of MDEV-17614 is extended and made more readable.
2022-05-06 22:16:42 +03:00
9614fde1aa Merge branch '10.2' into 10.3 2022-05-03 10:59:54 +02:00
a83c7ab1ea MDEV-11853: semisync thread can be killed after sync binlog but before ACK in the sync state
Problem:
========
If a primary is shutdown during an active semi-sync connection
during the period when the primary is awaiting an ACK, the primary
hard kills the active communication thread and does not ensure the
transaction was received by a replica. This can lead to an
inconsistent replication state.

Solution:
========
During shutdown, the primary should wait for an ACK or timeout
before hard killing a thread which is awaiting a communication. We
extend the `SHUTDOWN WAIT FOR SLAVES` logic to identify and ignore
any threads waiting for a semi-sync ACK in phase 1. Then, before
stopping the ack receiver thread, the shutdown is delayed until all
waiting semi-sync connections receive an ACK or time out. The
connections are then killed in phase 2.

Notes:
 1) There remains an unresolved corner case that affects this
patch. MDEV-28141: Slave crashes with Packets out of order when
connecting to a shutting down master. Specifically, If a slave is
connecting to a master which is actively shutting down, the slave
can crash with a "Packets out of order" assertion error. To get
around this issue in the MTR tests, the primary will wait a small
amount of time before phase 1 killing threads to let the replicas
safely stop (if applicable).
 2) This patch also fixes MDEV-28114: Semi-sync Master ACK Receiver
Thread Can Error on COM_QUIT

Reviewed By
============
Andrei Elkin <andrei.elkin@mariadb.com>
2022-04-22 12:59:54 -06:00
2be617d869 MDEV-25243 ASAN heap-use-after-free in Item_func_sp::execute_impl upon concurrent view DDL and I_S query with view and function 2022-04-21 09:51:11 +04:00
d62b0368ca Merge 10.4 into 10.5 2022-03-29 12:59:18 +03:00
97582f1c06 MDEV-27649 PS conflict handling causing node crash
Handling BF abort for prepared statement execution so that EXECUTE processing will continue
until parameter setup is complete, before BF abort bails out the statement execution.

THD class has new boolean member: wsrep_delayed_BF_abort, which is set if BF abort is observed
in do_command() right after reading client's packet, and if the client has sent PS execute command.
In such case, the deadlock error is not returned immediately back to client, but the PS execution
will be started. However, the PS execution loop, will now check if wsrep_delayed_BF_abort is set, and
stop the PS execution after the type information has been assigned for the PS.
With this, the PS protocol type information, which is present in the first PS EXECUTE command, is not lost
even if the first PS EXECUTE command was marked to abort.

Reviewed-by: Jan Lindström <jan.lindstrom@mariadb.com>
2022-03-18 08:30:25 +02:00
b73d852779 Merge 10.4 to 10.5 2022-03-17 17:03:24 +11:00
069139a549 Merge 10.3 to 10.4
extra2_read_len resolved by keeping the implementation
in sql/table.cc by exposed it for use by ha_partition.cc

Remove identical implementation in unireg.h
(ref: bfed2c7d57)
2022-03-16 16:39:10 +11:00
0e63023cb8 Merge branch 10.2 into 10.3 2022-03-16 12:49:13 +11:00
03c3dc6365 MDEV-23210 Assertion `(length % 4) == 0' failed in my_lengthsp_utf32 on ALTER TABLE, SELECT and INSERT
Problem:
Parse-time conversion from binary to tricky character sets like utf32
produced ill-formed strings. So, later a chash happened in debug builds,
or a wrong SHOW CREATE TABLE was returned in release builds.

Fix:

1. Backporting a few methods from 10.3:
  - THD::check_string_for_wellformedness()
  - THD::convert_string() overloads
  - THD::make_text_string_connection()

2. Adding a new method THD::reinterpret_string_from_binary(),
   which makes sure to either returns a well-formed string
   (optionally prepending with zero bytes), or returns an error.
2022-03-14 14:42:59 +04:00
81523baac6 Merge 10.4 into 10.5 2022-03-11 09:36:03 +02:00
22d2df8c6b Merge 10.3 into 10.4 2022-03-11 09:26:42 +02:00
1766a18e06 MDEV-19577 Replication does not work with innodb_autoinc_lock_mode=2
The first step for deprecating innodb_autoinc_lock_mode(see MDEV-27844) is:
- to switch statement binlog format to ROW if binlog format is MIXED and
the statement changes autoincremented fields
- issue warnings if innodb_autoinc_lock_mode == 2 and binlog format is
STATEMENT
2022-03-10 15:38:43 +03:00
e7cf871dda MDEV-24617 OPTIMIZE on a sequence causes unexpected ER_BINLOG_UNSAFE_STATEMENT
The warning out of OPTIMIZE
  Statement is unsafe because it uses a system function
was indeed counterfactual and was resulted by checking an
insufficiently strict property of lex' sql_command_flags.

Fixed with deploying an additional checking of weather
the current sql command that modifes a share->non_determinstic_insert
table is capable of generating ROW format events.
The extra check rules out the unsafety to OPTIMIZE et al, while the
existing check continues to do so to CREATE TABLE (which is
perculiarly tagged as ROW-event generative sql command).

As a side effect sql_sequence.binlog test gets corrected and
binlog_stm_unsafe_warning.test is reinforced to add up
an unsafe CREATE..SELECT test.
2022-03-10 13:38:07 +02:00
23368b76be Merge 10.4 into 10.5 2022-02-23 15:31:36 +02:00
0b849a441a WSREP: Fix GCC 12.0.1 -Wuninitialized
GCC 12 complains if a reference to an uninitialized object is
being passed to a constructor. The mysql_mutex_t, mysql_cond_t
would be initialized in the constructor body, which is executed
after the initializer list. There is no problem passing a pointer
instead of a reference. The wrapper classes do not dereference
the pointers in the constructor or destructor, so there does not
appear to be any correctness issue.
2022-02-23 07:18:00 +02:00
d4cb177603 Merge 10.4 into 10.5 2021-11-29 11:16:20 +02:00
4da2273876 Merge 10.3 into 10.4 2021-11-29 10:59:22 +02:00
289721de9a Merge 10.2 into 10.3 2021-11-29 10:33:06 +02:00
e9f171b4fe MDEV-27098 Subquery using the ALL keyword on TIME columns produces a wrong result 2021-11-20 21:49:25 +04:00
7efcc2794d MDEV-27072 Subquery using the ALL keyword on date columns produces a wrong result 2021-11-20 16:11:08 +04:00
ef2dbb8dbc MDEV-23328 Server hang due to Galera lock conflict resolution
Mutex order violation when wsrep bf thread kills a conflicting trx,
the stack is

          wsrep_thd_LOCK()
          wsrep_kill_victim()
          lock_rec_other_has_conflicting()
          lock_clust_rec_read_check_and_lock()
          row_search_mvcc()
          ha_innobase::index_read()
          ha_innobase::rnd_pos()
          handler::ha_rnd_pos()
          handler::rnd_pos_by_record()
          handler::ha_rnd_pos_by_record()
          Rows_log_event::find_row()
          Update_rows_log_event::do_exec_row()
          Rows_log_event::do_apply_event()
          Log_event::apply_event()
          wsrep_apply_events()

and mutexes are taken in the order

          lock_sys->mutex -> victim_trx->mutex -> victim_thread->LOCK_thd_data

When a normal KILL statement is executed, the stack is

          innobase_kill_query()
          kill_handlerton()
          plugin_foreach_with_mask()
          ha_kill_query()
          THD::awake()
          kill_one_thread()

        and mutexes are

          victim_thread->LOCK_thd_data -> lock_sys->mutex -> victim_trx->mutex

This patch is the plan D variant for fixing potetial mutex locking
order exercised by BF aborting and KILL command execution.

In this approach, KILL command is replicated as TOI operation.
This guarantees total isolation for the KILL command execution
in the first node: there is no concurrent replication applying
and no concurrent DDL executing. Therefore there is no risk of
BF aborting to happen in parallel with KILL command execution
either. Potential mutex deadlocks between the different mutex
access paths with KILL command execution and BF aborting cannot
therefore happen.

TOI replication is used, in this approach,  purely as means
to provide isolated KILL command execution in the first node.
KILL command should not (and must not) be applied in secondary
nodes. In this patch, we make this sure by skipping KILL
execution in secondary nodes, in applying phase, where we
bail out if applier thread is trying to execute KILL command.
This is effective, but skipping the applying of KILL command
could happen much earlier as well.

This also fixed unprotected calls to wsrep_thd_abort
that will use wsrep_abort_transaction. This is fixed
by holding THD::LOCK_thd_data while we abort transaction.

Reviewed-by: Jan Lindström <jan.lindstrom@mariadb.com>
2021-10-29 20:40:35 +02:00
d5bc05798f MDEV-25114: Crash: WSREP: invalid state ROLLED_BACK (FATAL)
Revert "MDEV-23328 Server hang due to Galera lock conflict resolution"

This reverts commit eac8341df4.
2021-10-29 20:38:11 +02:00
157b3a637f MDEV-23328 Server hang due to Galera lock conflict resolution
Mutex order violation when wsrep bf thread kills a conflicting trx,
the stack is

          wsrep_thd_LOCK()
          wsrep_kill_victim()
          lock_rec_other_has_conflicting()
          lock_clust_rec_read_check_and_lock()
          row_search_mvcc()
          ha_innobase::index_read()
          ha_innobase::rnd_pos()
          handler::ha_rnd_pos()
          handler::rnd_pos_by_record()
          handler::ha_rnd_pos_by_record()
          Rows_log_event::find_row()
          Update_rows_log_event::do_exec_row()
          Rows_log_event::do_apply_event()
          Log_event::apply_event()
          wsrep_apply_events()

and mutexes are taken in the order

          lock_sys->mutex -> victim_trx->mutex -> victim_thread->LOCK_thd_data

When a normal KILL statement is executed, the stack is

          innobase_kill_query()
          kill_handlerton()
          plugin_foreach_with_mask()
          ha_kill_query()
          THD::awake()
          kill_one_thread()

        and mutexes are

          victim_thread->LOCK_thd_data -> lock_sys->mutex -> victim_trx->mutex

This patch is the plan D variant for fixing potetial mutex locking
order exercised by BF aborting and KILL command execution.

In this approach, KILL command is replicated as TOI operation.
This guarantees total isolation for the KILL command execution
in the first node: there is no concurrent replication applying
and no concurrent DDL executing. Therefore there is no risk of
BF aborting to happen in parallel with KILL command execution
either. Potential mutex deadlocks between the different mutex
access paths with KILL command execution and BF aborting cannot
therefore happen.

TOI replication is used, in this approach,  purely as means
to provide isolated KILL command execution in the first node.
KILL command should not (and must not) be applied in secondary
nodes. In this patch, we make this sure by skipping KILL
execution in secondary nodes, in applying phase, where we
bail out if applier thread is trying to execute KILL command.
This is effective, but skipping the applying of KILL command
could happen much earlier as well.

This also fixed unprotected calls to wsrep_thd_abort
that will use wsrep_abort_transaction. This is fixed
by holding THD::LOCK_thd_data while we abort transaction.

Reviewed-by: Jan Lindström <jan.lindstrom@mariadb.com>
2021-10-29 10:00:17 +03:00
5c230b21bf MDEV-23328 Server hang due to Galera lock conflict resolution
Mutex order violation when wsrep bf thread kills a conflicting trx,
the stack is

          wsrep_thd_LOCK()
          wsrep_kill_victim()
          lock_rec_other_has_conflicting()
          lock_clust_rec_read_check_and_lock()
          row_search_mvcc()
          ha_innobase::index_read()
          ha_innobase::rnd_pos()
          handler::ha_rnd_pos()
          handler::rnd_pos_by_record()
          handler::ha_rnd_pos_by_record()
          Rows_log_event::find_row()
          Update_rows_log_event::do_exec_row()
          Rows_log_event::do_apply_event()
          Log_event::apply_event()
          wsrep_apply_events()

and mutexes are taken in the order

          lock_sys->mutex -> victim_trx->mutex -> victim_thread->LOCK_thd_data

When a normal KILL statement is executed, the stack is

          innobase_kill_query()
          kill_handlerton()
          plugin_foreach_with_mask()
          ha_kill_query()
          THD::awake()
          kill_one_thread()

        and mutexes are

          victim_thread->LOCK_thd_data -> lock_sys->mutex -> victim_trx->mutex

This patch is the plan D variant for fixing potetial mutex locking
order exercised by BF aborting and KILL command execution.

In this approach, KILL command is replicated as TOI operation.
This guarantees total isolation for the KILL command execution
in the first node: there is no concurrent replication applying
and no concurrent DDL executing. Therefore there is no risk of
BF aborting to happen in parallel with KILL command execution
either. Potential mutex deadlocks between the different mutex
access paths with KILL command execution and BF aborting cannot
therefore happen.

TOI replication is used, in this approach,  purely as means
to provide isolated KILL command execution in the first node.
KILL command should not (and must not) be applied in secondary
nodes. In this patch, we make this sure by skipping KILL
execution in secondary nodes, in applying phase, where we
bail out if applier thread is trying to execute KILL command.
This is effective, but skipping the applying of KILL command
could happen much earlier as well.

This also fixed unprotected calls to wsrep_thd_abort
that will use wsrep_abort_transaction. This is fixed
by holding THD::LOCK_thd_data while we abort transaction.

Reviewed-by: Jan Lindström <jan.lindstrom@mariadb.com>
2021-10-29 09:52:52 +03:00
aa7ca987db MDEV-25114: Crash: WSREP: invalid state ROLLED_BACK (FATAL)
Revert "MDEV-23328 Server hang due to Galera lock conflict resolution"

This reverts commit eac8341df4.
2021-10-29 09:52:40 +03:00
db50ea3ad3 MDEV-23328 Server hang due to Galera lock conflict resolution
Mutex order violation when wsrep bf thread kills a conflicting trx,
the stack is

          wsrep_thd_LOCK()
          wsrep_kill_victim()
          lock_rec_other_has_conflicting()
          lock_clust_rec_read_check_and_lock()
          row_search_mvcc()
          ha_innobase::index_read()
          ha_innobase::rnd_pos()
          handler::ha_rnd_pos()
          handler::rnd_pos_by_record()
          handler::ha_rnd_pos_by_record()
          Rows_log_event::find_row()
          Update_rows_log_event::do_exec_row()
          Rows_log_event::do_apply_event()
          Log_event::apply_event()
          wsrep_apply_events()

and mutexes are taken in the order

          lock_sys->mutex -> victim_trx->mutex -> victim_thread->LOCK_thd_data

When a normal KILL statement is executed, the stack is

          innobase_kill_query()
          kill_handlerton()
          plugin_foreach_with_mask()
          ha_kill_query()
          THD::awake()
          kill_one_thread()

        and mutexes are

          victim_thread->LOCK_thd_data -> lock_sys->mutex -> victim_trx->mutex

This patch is the plan D variant for fixing potetial mutex locking
order exercised by BF aborting and KILL command execution.

In this approach, KILL command is replicated as TOI operation.
This guarantees total isolation for the KILL command execution
in the first node: there is no concurrent replication applying
and no concurrent DDL executing. Therefore there is no risk of
BF aborting to happen in parallel with KILL command execution
either. Potential mutex deadlocks between the different mutex
access paths with KILL command execution and BF aborting cannot
therefore happen.

TOI replication is used, in this approach,  purely as means
to provide isolated KILL command execution in the first node.
KILL command should not (and must not) be applied in secondary
nodes. In this patch, we make this sure by skipping KILL
execution in secondary nodes, in applying phase, where we
bail out if applier thread is trying to execute KILL command.
This is effective, but skipping the applying of KILL command
could happen much earlier as well.

This also fixed unprotected calls to wsrep_thd_abort
that will use wsrep_abort_transaction. This is fixed
by holding THD::LOCK_thd_data while we abort transaction.

Reviewed-by: Jan Lindström <jan.lindstrom@mariadb.com>
2021-10-29 07:57:18 +03:00
f59f5c4a10 Revert MDEV-25114
Revert 88a4be75a5 and
9d97f92feb, which had been
prematurely pushed by accident.
2021-09-24 16:21:20 +03:00
88a4be75a5 MDEV-25114 Crash: WSREP: invalid state ROLLED_BACK (FATAL)
This patch is the plan D variant for fixing potetial mutex locking
order exercised by BF aborting and KILL command execution.

In this approach, KILL command is replicated as TOI operation.
This guarantees total isolation for the KILL command execution
in the first node: there is no concurrent replication applying
and no concurrent DDL executing. Therefore there is no risk of
BF aborting to happen in parallel with KILL command execution
either. Potential mutex deadlocks between the different mutex
access paths with KILL command execution and BF aborting cannot
therefore happen.

TOI replication is used, in this approach,  purely as means
to provide isolated KILL command execution in the first node.
KILL command should not (and must not) be applied in secondary
nodes. In this patch, we make this sure by skipping KILL
execution in secondary nodes, in applying phase, where we
bail out if applier thread is trying to execute KILL command.
This is effective, but skipping the applying of KILL command
could happen much earlier as well.

This patch also fixes mutex locking order and unprotected
THD member accesses on bf aborting case. We try to hold
THD::LOCK_thd_data during bf aborting. Only case where it
is not possible is at wsrep_abort_transaction before
call wsrep_innobase_kill_one_trx where we take InnoDB
mutexes first and then THD::LOCK_thd_data.

This will also fix possible race condition during
close_connection and while wsrep is disconnecting
connections.

Added wsrep_bf_kill_debug test case

Reviewed-by: Jan Lindström <jan.lindstrom@mariadb.com>
2021-09-24 09:47:31 +03:00
b4074069b2 MDEV-26657 : Initialize some fields in create_background_thd()
Avoid reading uninitialized memory by  thd_get_error_context_description().
Note, that THD::real_id can't be initialized at this stage, so it will be zeroed.
2021-09-21 19:14:07 +02:00
e38a05e20a Fix create_background_thd()
Allow the caller to have current_thd. Also do not store
PSI_CALL_get_thread() in the new THD, it is a thread local storage variable
that can become invalid any time, we do not control the lifetime of the
caller's thread.
2021-09-02 19:41:54 +02:00
8a33d36dac Fix GCC 11.2.0 -Wmaybe-uninitialized
TABLE_LIST::calc_md5(): Remove an untruthful const qualifier.

thd_get_query_start_data(): Pass empty_clex_str instead of
an uninitialized LEX_CSTRING.
2021-08-23 09:00:37 +03:00
4a25957274 Merge 10.4 into 10.5 2021-08-18 18:22:35 +03:00
f84e28c119 Merge 10.3 into 10.4 2021-08-18 16:51:52 +03:00
10db7fcfa6 MENT-977 log priv host / priv user.
Add server functions to provide necessary data.
2021-08-10 23:22:04 +04:00
ae6bdc6769 Merge branch '10.4' into 10.5 2021-07-31 23:19:51 +02:00
7841a7eb09 Merge branch '10.3' into 10.4 2021-07-31 22:59:58 +02:00
2b84e1c966 MDEV-23080: desync and pause node on BACKUP STAGE BLOCK_DDL
make BACKUP STAGE behave as FTWRL, desyncing and pausing the node
to prevent BF threads (appliers) from interfering with blocking stages.
This is needed because BF threads don't respect BACKUP MDL locks.

Reviewed-by: Jan Lindström <jan.lindstrom@mariadb.com>
2021-07-27 08:11:41 +03:00
6190a02f35 Merge branch '10.2' into 10.3 2021-07-21 20:11:07 +02:00
f64a4f672a follow-up MDEV-18166: rename marking functions
Reformulate mark_columns_used_by_index* function family in a more laconic
way:

mark_columns_used_by_index -> mark_index_columns
mark_columns_used_by_index_for_read_no_reset -> mark_index_columns_for_read
mark_columns_used_by_index_no_reset -> mark_index_columns_no_reset
static mark_index_columns -> do_mark_index_columns
2021-07-12 22:00:40 +03:00
675716e1cb 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.

# Conflicts:
#	sql/sql_cte.cc
#	sql/sql_cte.h
#	sql/sql_lex.cc
#	sql/sql_lex.h
#	sql/sql_view.cc
#	sql/sql_yacc.yy
#	sql/sql_yacc_ora.yy
2021-05-25 21:48:54 -07:00
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
1864a8ea93 Merge 10.2 into 10.3 2021-05-24 09:38:49 +03:00
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