The @@global.character_set_client variable could erroneously be set
to a non-default collation of its character set, which further made
the `SET NAMES DEFAULT` statement crash the server.
Fixing the code to make sure that the global value these variables:
@@character_set_client
@@character_set_connection
@@character_set_server
@@character_set_database
@@character_set_connection
point to the default compiled collations of the character set.
Also fixed that all unused variables are using the same variable comment.
The warning will be tested with the next commit that deprecates the
variable alter_algorithm.
Currently there are mechanism to mark a system variable as
deprecated, but they are only used to print warning messages
when a deprecated variable is set.
Leverage the existing mechanisms in order to make the
deprecation information available at the --help output of mysqld by:
* Moving the deprecation information (i.e `deprecation_substitute`
attribute) from the `sys_var` class into the `my_option` struct.
As every `sys_var` contains its own `my_option` struct, the access
to the deprecation information remains available to `sys_var`
objects. `my_getotp` functions, which works directly with
`my_option` structs, gain access to this information while building
the --help output.
* For plugin variables, leverages the `PLUGIN_VAR_DEPRECATED` flag
and set the `deprecation_substitute` attribute accordingly when
building the `my_option` objects.
* Change the `option_cmp` function to use the `deprecation_substitute`
attribute instead of the name when sorting the options. This way
deprecated options and the substitutes will be grouped together.
All new code of the whole pull request, including one or several files
that are either new files or modified ones, are contributed under the
BSD-new license. I am contributing on behalf of my employer
Amazon Web Services, Inc.
When the system variables @@debug_dbug was assigned to
some expression, Sys_debug_dbug::do_check() did not properly
convert the value from the expression character set to utf8.
So the value was erroneously re-interpretted as utf8 without
conversion. In case of a tricky expression character set
(e.g. utf16le), this led to unexpected results.
Fix:
Re-using Sys_var_charptr::do_string_check() in Sys_debug_dbug::do_check().
Updates to specific replication system variables need to target the
active primary connection to support multi-source replication. These
variables use the Sys_var_multi_source_ulonglong type. This class
uses offsets of the Master_info C++ class to generalize access to
its member variables.
The problem is that the Master_info class is not of standard layout,
and neither are many of its member variables, e.g. rli and
rli->relay_log. Because the class is not of standard layout, using
offsets to access member variables invokes undefined behavior.
This patch changes how Sys_var_multi_source_ulonglong accesses the
member variables of Master_info from using parameterized memory
offsets to “getter” function pointers.
Note that the size parameter and assertion are removed, as they are
no longer needed because the condition is guaranteed by compiler
type-safety checks.
Reviewed By:
============
Kristian Nielsen <knielsen@knielsen-hq.org>
Adding a global/session var `redirect_url' of string type. The initial
value is empty. Can be supplied in mysqld with --redirect-url or set
in --init-connect. A valid redirect_url should be of the format
{mysql,mariadb}://host[:port]
where <host> is an arbitrary string not containing colons, and <port>
is a number between 0 and 65535 inclusive.
The variable will be used by the server to notify clients that they
should connect to another server, specified by the value of the
variable, if not empty.
The notification is done by the inclusion of the variable in
session_track_system_variable.
Merge sys_var_charptr with sys_var_charptr_base, as well as merge
Sys_var_session_lexstring into Sys_var_lexstring. Also refactored
update methods of sys_var_charptr accordingly.
Because the class is more generic, session_update() calls
sys_var_charptr::session_update() which does not assume a buffer field
associated with THD, but instead call strdup/free, we get rid of
THD::default_master_connection_buff accordingly. This also makes THD
smaller by ~192 bytes, and there can be many thousands of concurrent
THDs.
The MDEV-29693 conflict resolution is from Monty, as well as is
a bug fix where ANALYZE TABLE wrongly built histograms for
single-column PRIMARY KEY.
Also includes a fix for safe_malloc error reporting.
Other things:
- Copied main.log_slow from 10.4 to avoid mtr issue
Disabled test:
- spider/bugfix.mdev_27239 because we started to get
+Error 1429 Unable to connect to foreign data source: localhost
-Error 1158 Got an error reading communication packets
- main.delayed
- Bug#54332 Deadlock with two connections doing LOCK TABLE+INSERT DELAYED
This part is disabled for now as it fails randomly with different
warnings/errors (no corruption).
Raise notes if indexes cannot be used:
- in case of data type or collation mismatch (diferent error messages).
- in case if a table field was replaced to something else
(e.g. Item_func_conv_charset) during a condition rewrite.
Added option to write warnings and notes to the slow query log for
slow queries.
New variables added/changed:
- note_verbosity, with is a set of the following options:
basic - All old notes
unusable_keys - Print warnings about keys that cannot be used
for select, delete or update.
explain - Print unusable_keys warnings for EXPLAIN querys.
The default is 'basic,explain'. This means that for old installations
the only notable new behavior is that one will get notes about
unusable keys when one does an EXPLAIN for a query. One can turn all
of all notes by either setting note_verbosity to "" or setting sql_notes=0.
- log_slow_verbosity has a new option 'warnings'. If this is set
then warnings and notes generated are printed in the slow query log
(up to log_slow_max_warnings times per statement).
- log_slow_max_warnings - Max number of warnings written to
slow query log.
Other things:
- One can now use =ALL for any 'set' variable to set all options at once.
For example using "note_verbosity=ALL" in a config file or
"SET @@note_verbosity=ALL' in SQL.
- mysqldump will in the future use @@note_verbosity=""' instead of
@sql_notes=0 to disable notes.
- Added "enum class Data_type_compatibility" and changing the return type
of all Field::can_optimize*() methods from "bool" to this new data type.
Reviewer & Co-author: Alexander Barkov <bar@mariadb.com>
- The code that prints out the notes comes mainly from Alexander
remove old deprecation helpers that were not used anywhere.
create new deprecation helpers and enforce their usage
this also removes inconsistencies in reporting deprecation:
sometimes it was ER_WARN_DEPRECATED_SYNTAX (1287),
sometimes ER_WARN_DEPRECATED_SYNTAX_NO_REPLACEMENT (1681),
sometimes a warning, sometimes a note.
it should always be
* ER_WARN_DEPRECATED_SYNTAX
* a warning (because it's something actionable, not purely informational)
This patch adds a way to override default collations
(or "character set collations") for desired character sets.
The SQL standard says:
> Each collation known in an SQL-environment is applicable to one
> or more character sets, and for each character set, one or more
> collations are applicable to it, one of which is associated with
> it as its character set collation.
In MariaDB, character set collations has been hard-coded so far,
e.g. utf8mb4_general_ci has been a hard-coded character set collation
for utf8mb4.
This patch allows to override (globally per server, or per session)
character set collations, so for example, uca1400_ai_ci can be set as a
character set collation for Unicode character sets
(instead of compiled xxx_general_ci).
The array of overridden character set collations is stored in a new
(session and global) system variable @@character_set_collations and
can be set as a comma separated list of charset=collation pairs, e.g.:
SET @@character_set_collations='utf8mb3=uca1400_ai_ci,utf8mb4=uca1400_ai_ci';
The variable is empty by default, which mean use the hard-coded
character set collations (e.g. utf8mb4_general_ci for utf8mb4).
The variable can also be set globally by passing to the server startup command
line, and/or in my.cnf.
Turn the remaining three `binlog*` options binlog_do_db, binlog_ignore_db,
binlog_rows_event_max_size into global variables so that they can be
visible from the SQL user level. This is for audit / secure
configuration check purposes.
Create new MTR tests to make sure that the newly created global
variables can be visible from the command line interface.
Behavior before the code change:
MariaDB [(none)]> SHOW GLOBAL VARIABLES WHERE
-> Variable_name LIKE 'binlog_do_db' OR
-> Variable_name LIKE 'binlog_ignore_db' OR
-> Variable_name LIKE 'binlog_row_event_max_size';
Empty set (0.001 sec)
Behavior after the code change:
MariaDB [(none)]> SHOW GLOBAL VARIABLES WHERE
-> Variable_name LIKE 'binlog_do_db' OR
-> Variable_name LIKE 'binlog_ignore_db' OR
-> Variable_name LIKE 'binlog_row_event_max_size';
+---------------------------+-------+
| Variable_name | Value |
+---------------------------+-------+
| binlog_do_db | |
| binlog_ignore_db | |
| binlog_row_event_max_size | 8192 |
+---------------------------+-------+
3 rows in set (0.001 sec)
Note:
For `binlog_do_db` and `binlog_ignore_db`, we add a new class
`Sys_var_binlog_filter` to handle the dynamically-composable command line
options for `binlog_do_db` and `binlog_ignore_db`. Below
is the motivation:
When the users start the server with the option
--binlog-do-db="database1" --binlog-do-db="database2"
The expected behavior is that the system should allow replication for
both `database1` and `database2`, which is the logic of the original
code.
However, when turning the variables into system variables, the
functionality does not exist any more, since system variables will only
handle the last occurrence of the option, and in this case, the system
will only be able to handle `database2`.
Copyright:
All new code of the whole pull request, including one or several files
that are either new files or modified ones, are contributed under the BSD-new
license. I am contributing on behalf of my employer Amazon Web Services, Inc.
In MariaDB, we have a confusing problem where:
* The transaction_isolation option can be set in a configuration file, but it cannot be set dynamically.
* The tx_isolation system variable can be set dynamically, but it cannot be set in a configuration file.
Therefore, we have two different names for the same thing in different contexts. This is needlessly confusing, and it complicates the documentation. The same thing applys for transaction_read_only.
MySQL 5.7 solved this problem by making them into system variables. https://dev.mysql.com/doc/relnotes/mysql/5.7/en/news-5-7-20.html
This commit takes a similar approach by adding new system variables and marking the original ones as deprecated. This commit also resolves some legacy problems related to SET STATEMENT and transaction_isolation.
avoid contaminating my_getopt with sysvar implementation details.
adjust variable values after my_getopt, like it's done for others.
this fixes --help to show correct values.
