The special logic used by the memory storage engine
to keep slaves in sync with the master on a restart can
break replication. In particular, after a restart, the
master writes DELETE statements in the binlog for
each MEMORY-based table so the slave can empty its
data. If the DELETE is not executable, e.g. due to
invalid triggers, the slave will error and fail, whereas
the master will never see the problem.
Instead of DELETE statements, use TRUNCATE to
keep slaves in-sync with the master, thereby bypassing
triggers.
Reviewed By:
===========
Kristian Nielsen <knielsen@knielsen-hq.org>
Andrei Elkin <andrei.elkin@mariadb.com>
One of possible use cases that reproduces the memory leakage listed below:
set timestamp= unix_timestamp('2000-01-01 00:00:00');
create or replace table t1 (x int) with system versioning
partition by system_time interval 1 hour auto
partitions 3;
create table t2 (x int);
create trigger tr after insert on t2 for each row update t1 set x= 11;
create or replace procedure sp2() insert into t2 values (5);
set timestamp= unix_timestamp('2000-01-01 04:00:00');
call sp2;
set timestamp= unix_timestamp('2000-01-01 13:00:00');
call sp2; # <<=== Memory leak happens there. In case MariaDB server is built
with the option -DWITH_PROTECT_STATEMENT_MEMROOT,
the second execution would hit assert failure.
The reason of leaking a memory is that once a new partition be created
the table should be closed and re-opened. It results in calling the function
extend_table_list() that indirectly invokes the function sp_add_used_routine()
to add routines implicitly used by the statement that makes a new memory
allocation.
To fix it, don't remove routines and tables the statement implicitly depends
on when a table being closed for subsequent re-opening.
In cmake -DWITH_UBSAN=ON builds with clang but not with GCC,
-fsanitize=undefined will flag several runtime errors on
function pointer mismatch related to the lock-free hash table LF_HASH.
Let us use matching function signatures and remove function pointer
casts in order to avoid potential bugs due to undefined behaviour.
These errors could be caught at compilation time by
-Wcast-function-type-strict, which is available starting with clang-16,
but not available in any version of GCC as of now. The old GCC flag
-Wcast-function-type is enabled as part of -Wextra, but it specifically
does not catch these errors.
Reviewed by: Vladislav Vaintroub
- Moved writing to binlog_cache from close_thread_tables() to
binlog_commit().
- In select_create() delete cached row events instead of flushing them
to disk. This was done to avoid possible disk write error in this code.
This patch extends the timestamp from
2038-01-19 03:14:07.999999 to 2106-02-07 06:28:15.999999
for 64 bit hardware and OS where 'long' is 64 bits.
This is true for 64 bit Linux but not for Windows.
This is done by treating the 32 bit stored int as unsigned instead of
signed. This is safe as MariaDB has never accepted dates before the epoch
(1970).
The benefit of this approach that for normal timestamp the storage is
compatible with earlier version.
However for tables using system versioning we before stored a
timestamp with the year 2038 as the 'max timestamp', which is used to
detect current values. This patch stores the new 2106 year max value
as the max timestamp. This means that old tables using system
versioning needs to be updated with mariadb-upgrade when moving them
to 11.4. That will be done in a separate commit.
Fixed that no tables from 'mysql' schema are included in userstat.
A beneif of this is that the server is not reading statistics tables
if mysql.proc or other tables in mysql is accessed.
This is to update the plugin to be compatible with Percona's
query_response_time plugin, with some additions.
Some of the tests are taken from Percona server.
- Added plugins QUERY_RESPONSE_TIME_READ, QUERY_RESPONSE_TIME_WRITE and
QUERY_RESPONSE_TIME_READ_WRITE.
- Added option query_response_time_session_stats, with possible values
GLOBAL, ON or OFF, to the query_response_time plugin.
Notes:
- All modules are dependent on QUERY_RESPONSE_READ_TIME. This must always
be enabled if any of the other modules are used.
This will be auto-enabled in the near future.
- Accounting are done per statement. Stored functions are regarded
as part of the original statement.
- For stored procedures the accounting are done per statement executed
in the stored procedure. CALL will not be accounted because of this.
- FLUSH commands will not be accounted for. This is to ensure that
FLUSH QUERY_RESPONSE_TIME is not part of the statistics.
(This helps when testing with mtr and otherwise).
- FLUSH QUERY_RESPONSE_TIME_READ and FLUSH QUERY_RESPONSE_TIME_READ
only resets the corresponding status.
- FLUSH QUERY_RESPONSE_TIME and FLUSH QUERY_RESPONSE_TIME_READ_WRITE or
changing the value of query_response_time_range_base followed by
any FLUSH of QUERY_RESPOSNSE_TIME resets all status.
The patch for MDEV-31340 fixed the following bugs:
MDEV-33084 LASTVAL(t1) and LASTVAL(T1) do not work well with lower-case-table-names=0
MDEV-33085 Tables T1 and t1 do not work well with ENGINE=CSV and lower-case-table-names=0
MDEV-33086 SHOW OPEN TABLES IN DB1 -- is case insensitive with lower-case-table-names=0
MDEV-33088 Cannot create triggers in the database `MYSQL`
MDEV-33103 LOCK TABLE t1 AS t2 -- alias is not case sensitive with lower-case-table-names=0
MDEV-33108 TABLE_STATISTICS and INDEX_STATISTICS are case insensitive with lower-case-table-names=0
MDEV-33109 DROP DATABASE MYSQL -- does not drop SP with lower-case-table-names=0
MDEV-33110 HANDLER commands are case insensitive with lower-case-table-names=0
MDEV-33119 User is case insensitive in INFORMATION_SCHEMA.VIEWS
MDEV-33120 System log table names are case insensitive with lower-cast-table-names=0
Backporting the fixes from 11.5 to 10.5
This patch also fixes:
MDEV-33050 Build-in schemas like oracle_schema are accent insensitive
MDEV-33084 LASTVAL(t1) and LASTVAL(T1) do not work well with lower-case-table-names=0
MDEV-33085 Tables T1 and t1 do not work well with ENGINE=CSV and lower-case-table-names=0
MDEV-33086 SHOW OPEN TABLES IN DB1 -- is case insensitive with lower-case-table-names=0
MDEV-33088 Cannot create triggers in the database `MYSQL`
MDEV-33103 LOCK TABLE t1 AS t2 -- alias is not case sensitive with lower-case-table-names=0
MDEV-33109 DROP DATABASE MYSQL -- does not drop SP with lower-case-table-names=0
MDEV-33110 HANDLER commands are case insensitive with lower-case-table-names=0
MDEV-33119 User is case insensitive in INFORMATION_SCHEMA.VIEWS
MDEV-33120 System log table names are case insensitive with lower-cast-table-names=0
- Removing the virtual function strnncoll() from MY_COLLATION_HANDLER
- Adding a wrapper function CHARSET_INFO::streq(), to compare
two strings for equality. For now it calls strnncoll() internally.
In the future it will turn into a virtual function.
- Adding new accent sensitive case insensitive collations:
- utf8mb4_general1400_as_ci
- utf8mb3_general1400_as_ci
They implement accent sensitive case insensitive comparison.
The weight of a character is equal to the code point of its
upper case variant. These collations use Unicode-14.0.0 casefolding data.
The result of
my_charset_utf8mb3_general1400_as_ci.strcoll()
is very close to the former
my_charset_utf8mb3_general_ci.strcasecmp()
There is only a difference in a couple dozen rare characters, because:
- the switch from "tolower" to "toupper" comparison, to make
utf8mb3_general1400_as_ci closer to utf8mb3_general_ci
- the switch from Unicode-3.0.0 to Unicode-14.0.0
This difference should be tolarable. See the list of affected
characters in the MDEV description.
Note, utf8mb4_general1400_as_ci correctly handles non-BMP characters!
Unlike utf8mb4_general_ci, it does not treat all BMP characters
as equal.
- Adding classes representing names of the file based database objects:
Lex_ident_db
Lex_ident_table
Lex_ident_trigger
Their comparison collation depends on the underlying
file system case sensitivity and on --lower-case-table-names
and can be either my_charset_bin or my_charset_utf8mb3_general1400_as_ci.
- Adding classes representing names of other database objects,
whose names have case insensitive comparison style,
using my_charset_utf8mb3_general1400_as_ci:
Lex_ident_column
Lex_ident_sys_var
Lex_ident_user_var
Lex_ident_sp_var
Lex_ident_ps
Lex_ident_i_s_table
Lex_ident_window
Lex_ident_func
Lex_ident_partition
Lex_ident_with_element
Lex_ident_rpl_filter
Lex_ident_master_info
Lex_ident_host
Lex_ident_locale
Lex_ident_plugin
Lex_ident_engine
Lex_ident_server
Lex_ident_savepoint
Lex_ident_charset
engine_option_value::Name
- All the mentioned Lex_ident_xxx classes implement a method streq():
if (ident1.streq(ident2))
do_equal();
This method works as a wrapper for CHARSET_INFO::streq().
- Changing a lot of "LEX_CSTRING name" to "Lex_ident_xxx name"
in class members and in function/method parameters.
- Replacing all calls like
system_charset_info->coll->strcasecmp(ident1, ident2)
to
ident1.streq(ident2)
- Taking advantage of the c++11 user defined literal operator
for LEX_CSTRING (see m_strings.h) and Lex_ident_xxx (see lex_ident.h)
data types. Use example:
const Lex_ident_column primary_key_name= "PRIMARY"_Lex_ident_column;
is now a shorter version of:
const Lex_ident_column primary_key_name=
Lex_ident_column({STRING_WITH_LEN("PRIMARY")});
Some fixes related to commit f838b2d799 and
Rows_log_event::do_apply_event() and Update_rows_log_event::do_exec_row()
for system-versioned tables were provided by Nikita Malyavin.
This was required by test versioning.rpl,trx_id,row.
In case there is a view that queried from a stored routine or
a prepared statement and this temporary table is dropped between
executions of SP/PS, then it leads to hitting an assertion
at the SELECT_LEX::fix_prepare_information. The fired assertion
was added by the commit 85f2e4f8e8
(MDEV-32466: Potential memory leak on executing of create view statement).
Firing of this assertion means memory leaking on execution of SP/PS.
Moreover, if the added assert be commented out, different result sets
can be produced by the statement SELECT * FROM the hidden table.
Both hitting the assertion and different result sets have the same root
cause. This cause is usage of temporary table's metadata after the table
itself has been dropped. To fix the issue, reload the cache of stored
routines. To do it cache of stored routines is reset at the end of
execution of the function dispatch_command(). Next time any stored routine
be called it will be loaded from the table mysql.proc. This happens inside
the method Sp_handler::sp_cache_routine where loading of a stored routine
is performed in case it missed in cache. Loading is performed unconditionally
while previously it was controlled by the parameter lookup_only. By that
reason the signature of the method Sroutine_hash_entry::sp_cache_routine
was changed by removing unused parameter lookup_only.
Clearing of sp caches affects the test main.lock_sync since it forces
opening and locking the table mysql.proc but the test assumes that each
statement locks its tables once during its execution. To keep this invariant
the debug sync points with names "before_lock_tables_takes_lock" and
"after_lock_tables_takes_lock" are not activated on handling the table
mysql.proc
This will makes it easier to find out what replication workers are
doing and what they are waiting for.
Things changed in processlist:
- Slave_SQL time was not consistent. Now time for state "Slave has
read all relay log; waiting for more updates" shows how long it has
waited for getting the next event.
- Slave_worker threads did often show "Closing tables" for a long
time. Now the state is reverted to the previous state after
"Closing tables" is done.
- Commit and Rollback states where not shown for replication (and some
other threads). Now Commit and Rollback states are always shown and
the state is reverted to previous state when the Commit/Rollback
have finished.
Code changes:
- Added thd->set_time_for_next_stage() for parallel replication when
when starting to wait for prior transactions to commit, group commit,
and FTWRL and for free space in thread pool.
Before we reset the time only after the above events.
- Moved THD_STAGE_INFO(stage_rollback) and THD_STAGE_INFO(stage_commit)
from sql_parse.cc to transaction.cc to ensure this is done for
all commits and not only 'normal connection queries'.
Test case changes:
- close_thread_tables() reverting stage to previous stage caused the
counter in performance_schema to be increased. In many case it is
the 'sql/starting' stage that was effected.
- We only change to "Commit" stage if there is a need for a commit.
This caused some "Commit" stages to disapper from perfschema reports.
TODO in 11.#:
- Slave_IO always showes "Waiting for master to send event" and the time is
from SLAVE START. We should in 11.# change this to be the time since
reading the last event.
This patch fixes the issue with passing the DEFAULT or IGNORE values to
positional parameters for some kind of SQL statements to be executed
as prepared statements.
The main idea of the patch is to associate an actual value being passed
by the USING clause with the positional parameter represented by
the Item_param class. Such association must be performed on execution of
UPDATE statement in PS/SP mode. Other corner cases that results in
server crash is on handling CREATE TABLE when positional parameter
placed after the DEFAULT clause or CALL statement and passing either
the value DEFAULT or IGNORE as an actual value for the positional parameter.
This case is fixed by checking whether an error is set in diagnostics
area at the function pack_vcols() on return from the function pack_expression()
