Added capability to create a trigger associated with several trigger events.
For this goal, the syntax of the CREATE TRIGGER statement was extended
to support the syntax structure { event [ OR ... ] } for the `trigger_event`
clause. Since one trigger will be able to handle several events it should be
provided a way to determine what kind of event is handled on execution of a
trigger. For this goal support of the clauses INSERTING, UPDATING , DELETING
was added by this patch. These clauses can be used inside a trigger body
to detect what kind of trigger action is currently processed using the following
boilerplate:
IF INSERTING THEN ...
ELSIF UPDATING THEN ...
ELSIF DELETING THEN ...
In case one of the clauses INSERTING, UPDATING, DELETING specified in
a trigger's body not matched with a trigger event type, the error
ER_INCOMPATIBLE_EVENT_FLAG is emitted.
After this patch be pushed, one Trigger object will be associated with several
trigger events. It means that the array Table_triggers_list::triggers can
contain several pointers to the same Trigger object in array members
corresponding to different events. Moreover, support of several trigger events
for the same trigger requires that the data members `next` and `action_order`
of the Trigger class be converted to arrays to store relating information per
trigger event base.
Ability to specify the same trigger for different event types results in
necessity to handle invalid cases on execution of the multi-event trigger,
when the OLD or NEW qualifiers doesn't match a current event type against that
the trigger is run. The clause OLD should produce the NULL value for INSERT event,
whereas the clause NEW should produce the NULL value for DELETE event.
Atomic CREATE OR REPLACE allows to keep an old table intact if the
command fails or during the crash. That is done by renaming the
original table to temporary name, as a backup and restoring it if the
CREATE fails. When the command is complete and logged the backup
table is deleted.
Atomic replace algorithm
Two DDL chains are used for CREATE OR REPLACE:
ddl_log_state_create (C) and ddl_log_state_rm (D).
1. (C) Log rename of ORIG to TMP table (Rename TMP to original).
2. Rename orignal to TMP.
3. (C) Log CREATE_TABLE_ACTION of ORIG (drops ORIG);
4. Do everything with ORIG (like insert data)
5. (D) Log drop of TMP
6. Write query to binlog (this marks (C) to be closed in
case of failure)
7. Execute drop of TMP through (D)
8. Close (C) and (D)
If there is a failure before 6) we revert the changes in (C)
Chain (D) is only executed if 6) succeded (C is closed on
crash recovery).
Foreign key errors will be found at the 1) stage.
Additional notes
- CREATE TABLE without REPLACE and temporary tables is not affected
by this commit.
set @@drop_before_create_or_replace=1 can be used to
get old behaviour where existing tables are dropped
in CREATE OR REPLACE.
- CREATE TABLE is reverted if binlogging the query fails.
- Engines having HTON_EXPENSIVE_RENAME flag set are not affected by
this commit. Conflicting tables marked with this flag will be
deleted with CREATE OR REPLACE.
- Replication execution is not affected by this commit.
- Replication will first drop the conflicting table and then
creating the new one.
- CREATE TABLE .. SELECT XID usage is fixed and now there is no need
to log DROP TABLE via DDL_CREATE_TABLE_PHASE_LOG (see comments in
do_postlock()). XID is now correctly updated so it disables
DDL_LOG_DROP_TABLE_ACTION. Note that binary log is flushed at the
final stage when the table is ready. So if we have XID in the
binary log we don't need to drop the table.
- Three variations of CREATE OR REPLACE handled:
1. CREATE OR REPLACE TABLE t1 (..);
2. CREATE OR REPLACE TABLE t1 LIKE t2;
3. CREATE OR REPLACE TABLE t1 SELECT ..;
- Test case uses 6 combinations for engines (aria, aria_notrans,
myisam, ib, lock_tables, expensive_rename) and 2 combinations for
binlog types (row, stmt). Combinations help to check differences
between the results. Error failures are tested for the above three
variations.
- expensive_rename tests CREATE OR REPLACE without atomic
replace. The effect should be the same as with the old behaviour
before this commit.
- Triggers mechanism is unaffected by this change. This is tested in
create_replace.test.
- LOCK TABLES is affected. Lock restoration must be done after new
table is created or TMP is renamed back to ORIG
- Moved ddl_log_complete() from send_eof() to finalize_ddl(). This
checkpoint was not executed before for normal CREATE TABLE but is
executed now.
- CREATE TABLE will now rollback also if writing to the binary
logging failed. See rpl_gtid_strict.test
backup ddl log changes
- In case of a successfull CREATE OR REPLACE we only log
the CREATE event, not the DROP TABLE event of the old table.
ddl_log.cc changes
ddl_log_execute_action() now properly return error conditions.
ddl_log_disable_entry() added to allow one to disable one entry.
The entry on disk is still reserved until ddl_log_complete() is
executed.
On XID usage
Like with all other atomic DDL operations XID is used to avoid
inconsistency between master and slave in the case of a crash after
binary log is written and before ddl_log_state_create is closed. On
recovery XIDs are taken from binary log and corresponding DDL log
events get disabled. That is done by
ddl_log_close_binlogged_events().
On linking two chains together
Chains are executed in the ascending order of entry_pos of execute
entries. But entry_pos assignment order is undefined: it may assign
bigger number for the first chain and then smaller number for the
second chain. So the execution order in that case will be reverse:
second chain will be executed first.
To avoid that we link one chain to another. While the base chain
(ddl_log_state_create) is active the secondary chain
(ddl_log_state_rm) is not executed. That is: only one chain can be
executed in two linked chains.
The interface ddl_log_link_chains() was defined in "MDEV-22166
ddl_log_write_execute_entry() extension".
Atomic info parameters in HA_CREATE_INFO
Many functions in CREATE TABLE pass the same parameters. These
parameters are part of table creation info and should be in
HA_CREATE_INFO (or whatever). Passing parameters via single
structure is much easier for adding new data and
refactoring.
InnoDB changes
Added ha_innobase::can_be_renamed_to_backup() to check if
a table with foreign keys can be renamed.
Aria changes:
- Fixed issue in Aria engine with CREATE + locked tables
that data was not properly commited in some cases in
case of crashes.
Known issues:
- InnoDB tables with foreign key definitions are not fully supported
with atomic create and replace:
- ha_innobase::can_be_renamed_to_backup() can detect some cases
where InnoDB does not support renaming table with foreign key
constraints. In this case MariaDB will drop the old table before
creating the new one.
The detected cases are:
- The new and old table is using the same foreign key constraint
name.
- The old table has self referencing constraints.
- If the old and new table uses the same name for a constraint the
create of the new table will fail. The orignal table will be
restored in this case.
- The above issues will be fixed in a future commit.
- CREATE OR REPLACE TEMPORARY table is not full atomic. Any conflicting
table will always be dropped before creating a new one. (Old behaviour).
This is part of MDEV-25292 Atomic CREATE OR REPLACE TABLE.
Removed default values for arguments, added flags argument to specify
filename flags (FN_TO_IS_TMP, FN_FROM_IS_TMP) and forward the flag to
build_table_name().
Original patch from: Aleksey Midenkov <midenok@gmail.com>
* `get_master_version_and_clock()` de-duplicate label using fall-through
* `io_slave_killed()` & `check_io_slave_killed()`:
* reüse the result from the level lower
* add distinguishing docs
* `try_to_reconnect()`: extract `'` from `if`-`else`
* `handle_slave_io()`: Both `while`s have the same condition;
looks like the outer `while` can simply be an `if`.
* `connect_to_master()`:
* assume `mysql_errno()` is not 0 on connection error
* utilize 0’s falsiness in the loop
* extend docs
* `sql/sql_show.cc`: refactor SHOW ALL REPLICAS filter’s condition
* `sql/mysqld.cc`: init `master-retry-count` with `master_retry_count`
Reviewed-by: Kristian Nielsen <knielsen@knielsen-hq.org>
When the IO thread (re)connect to a primary,
no updates are available besides unique errors that cause the failure.
These new `Master_info` numbers supplement SHOW SLAVE STATUS’s (most-
recent) ‘Connecting’ state with statistics on (re)connect attempts:
* `Connects_Tried`: how many retries have been attempted so far
This was previously a local variable that only counted re-attempts;
it’s now meaningful even after the “Connecting” state concludes.
* `Master_Retry_Count` (from MDEV-25674): out of how many configured
Side-note: Some of the tests updated by this commit dump the entire
SHOW SLAVE STATUS, which might include non-deterministic entries.
Reviewed-by: Kristian Nielsen <knielsen@knielsen-hq.org>
Reviewed-by: Brandon Nesterenko <brandon.nesterenko@mariadb.com>
Added caching of database directories that did not have a db.opt file.
This was common for older MariaDB installaiton or if a user created
a database with 'mkdir'.
Other things:
- Give a note "no db.opt file" if one uses SHOW CREATE DATABASE one
a database without a db.opt file.
* rpl.rpl_system_versioning_partitions updated for MDEV-32188
* innodb.row_size_error_log_warnings_3 changed error for MDEV-33658
(checks are done in a different order)
Update all integer columns of SHOW REPLICA STATUS (technically
INFORMATION_SCHEMA.SLAVE_STATUS) to unsigned because, well, they are (:.
Some `uint32` ones were accidentally using the `Field::store(double nr)`
overload because they forgot the `, true` for
`Field::store(longlong nr, bool unsigned_val)`.
The mistake’s harmless, fortunately, as `double` supports over 15
significant decimal digits, well over `uint32`’s 9-and-a-half.
Resize the types and widths of SHOW REPLICA STATUS
(technically `INFORMATION_SCHEMA.SLAVE_STATUS`)
columns to better match their possible values
In case of intentionally but absurdly long lists,
text columns that list an uncapped number of elements
have expanded to accept as many bytes as we could support.
Particularly, the first-gen `Replicate_` filters were
incorrectly typed as singlular `Name()`s during MDEV-33526.
Under `Name`s’ 64-char limit, they could overflow
(read: truncate) even before their lengths got absurd.
In response to `‘MAX_SLAVE_ERRMSG’ was not declared in this scope` in
Embedded builds, a new `#ifdef HAVE_REPLICATION` guard wraps
`slave_status_info` to skip this unused data in Replication-less builds.
For testing, this commit forward-ports a modified cherry-pick of #3795
(the latter targets our oldest maintained LTS as part of MDEV-35948).
> Assert that 1st-gen `replicate_*` filter variables display
> their input – including long but reasonable lists –
> correctly (without truncation) in
> * direct SELECT
> * [semi-new] INFORMATION_SCHEMA.GLOBAL_VARIABLES.VARIABLE_VALUE
> * [new] SHOW REPLICA STATUS
Reviewed-by: Brandon Nesterenko <brandon.nesterenko@mariadb.com>
Item:print_for_table_def() uses QT_TO_SYSTEM_CHARSET to print
the DEFAULT expression into FRM file during CREATE TABLE.
Therefore, the expression is encoded in utf8 in FRM.
get_field_default_value() erroneously used field->charset() to
print the DEFAULT expression at SHOW CREATE TABLE time.
Fixing get_field_default_value() to use &my_charset_utf8mb4_general_ci instead.
This makes DEFAULT work in the way way with:
- virtual column expressions:
if (field->vcol_info)
{
StringBuffer<MAX_FIELD_WIDTH> str(&my_charset_utf8mb4_general_ci);
field->vcol_info->print(&str);
- check constraint expressions:
if (field->check_constraint)
{
StringBuffer<MAX_FIELD_WIDTH> str(&my_charset_utf8mb4_general_ci);
field->check_constraint->print(&str);
Additional cleanup:
Fixing system_charset_info to &my_charset_utf8mb4_general_ci in a few
places to make non-BMP characters work in DEFAULT, virtual column,
check constraint expressions.
- Needless engaged_ removed;
- SCOPE_VALUE, SCOPE_SET, SCOPE_CLEAR macros for neater declaration;
- IF_CLASS / IF_NOT_CLASS SFINAE checkers to pass arg by value or
reference;
- inline keyword;
- couple of refactorings of temporary free_list.
Example:
{
auto _= make_scope_value(var, tmp_value);
}
make_scope_value(): a function which returns RAII object which temporary
changes a value of a variable
detail::Scope_value: actual implementation of such RAII class.
It shouldn't be used directly! That's why it's inside a namespace detail.
use the same condition in
fill_schema_table_from_frm() when open_table_from_share() fails, as in
fill_schema_table_from_frm() when tdc_aquire_share() fails and as in
fill_schema_table_from_open() when open_table_from_share() fails
get_all_tables() skipped tables if the user has no privileges on
the schema itself and no granted privilege on any tables in the schema.
that is, it was skipping performance_schema tables (privileges
on them aren't explicitly granted, but internally hard-coded)
To fix:
* extend ACL_internal_table_access::check() method with
`bool any_combination_will_do`
* fix all perfschema privilege checks to take it into account.
* don't reuse table_acl_check object for all tables, initialize it
for every table otherwise GRANT_INTERNAL_INFO will leak
* remove incorrect privilege check from get_all_tables()
Added Query_time (total time spent running queries) to status_variables.
Other things:
- Added SHOW_MICROSECOND_STATUS type that shows an ulonglong variable
in microseconds converted to a double (in seconds).
- Changed Busy_time and Cpu_time to use SHOW_MICROSECOND_STATUS, which
simplified the code and avoids some double divisions for each query.
Reviewed-by: Sergei Golubchik <serg@mariadb.org>
This is done by mapping most of the existing MySQL unicode 0900 collations
to MariadB 1400 unicode collations. The assumption is that 1400 is a super
set of 0900 for all practical purposes.
I also added a new function 'compare_collations()' and changed most code
to use this instead of comparing character sets directly.
This enables one to seamlessly mix-and-match the corresponding 0900 and
1400 sets. Field comparision and alter table treats the character sets
as identical.
All MySQL 8.0 0900 collations are supported except:
- utf8mb4_ja_0900_as_cs
- utf8mb4_ja_0900_as_cs_ks
- utf8mb4_ru_0900_as_cs
- utf8mb4_zh_0900_as_cs
These do not have corresponding entries in the MariadB 01400 collations.
Other things:
- Added COMMENT colum to information_schema.collations. For utf8mb4_0900
colletions it contains the corresponding alias collation.
Partial commit of the greater MDEV-34348 scope.
MDEV-34348: MariaDB is violating clang-16 -Wcast-function-type-strict
Reviewed By:
============
Marko Mäkelä <marko.makela@mariadb.com>
Partial commit of the greater MDEV-34348 scope.
MDEV-34348: MariaDB is violating clang-16 -Wcast-function-type-strict
Change the type of my_hash_get_key to:
1) Return const
2) Change the context parameter to be const void*
Also fix casting in hash adjacent areas.
Reviewed By:
============
Marko Mäkelä <marko.makela@mariadb.com>
Sending "This function has the same name" during I_S quries was too verbose.
Suppressing these warnings.
Now warnings are sent only during CREATE FUNCTION and during function call.
MDEV-33407 Parser support for vector indexes
The syntax is
create table t1 (... vector index (v) ...);
limitation:
* v is a binary string and NOT NULL
* only one vector index per table
* temporary tables are not supported
MDEV-33404 Engine-independent indexes: subtable method
added support for so-called "high level indexes", they are not visible
to the storage engine, implemented on the sql level. For every such
an index in a table, say, t1, the server implicitly creates a second
table named, like, t1#i#05 (where "05" is the index number in t1).
This table has a fixed structure, no frm, not accessible directly,
doesn't go into the table cache, needs no MDLs.
MDEV-33406 basic optimizer support for k-NN searches
for a query like SELECT ... ORDER BY func() optimizer will use
item_func->part_of_sortkey() to decide what keys can be used
to resolve ORDER BY.
let the caller tell init_tmp_table_share() whether the table
should be thread_specific or not.
In particular, internal tmp tables created in the slave thread
are perfectly thread specific
create templates
thd->alloc<X>(n) to use instead of (X*)thd->alloc(sizeof(X)*n)
and the same for thd->calloc(). By the default the type is char,
so old usage of thd->alloc(size) works too.
