prep_alter_part_table upon re-partitioning by system time
memcmp() tries to compare beyond the last member of interval because
sizeof(Vers_part_info::interval) is 80. It is sizeof of variable,
sizeof of type is 76.
Now we compare interval_t struct C++ way.
- agressively -> aggressively
- exising -> existing
- occured -> occurred
- releated -> related
- seperated -> separated
- sucess -> success
- use use -> use
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.
For commands
(1) alter table t1 add partition (partition p2);
(2) alter table t1 add partition (partition px history);
It printed the same error message:
Wrong partitioning type, expected type: `SYSTEM_TIME`
For (1) it is not clear from the syntax that we are trying to add
HASH partition. For (2) it is not clear that the table partitioning is
different than SYSTEM_TIME. Now it prints what type we are trying to
add to what type of partitioning.
Fixed warning unused function rename_field_in_list() for compilation
without partitioning.
For commands
(1) alter table t1 add partition (partition p2);
(2) alter table t1 add partition (partition px history);
It printed the same error message:
Wrong partitioning type, expected type: `SYSTEM_TIME`
For (1) it is not clear from the syntax that we are trying to add
HASH partition. For (2) it is not clear that the table partitioning is
different than SYSTEM_TIME. Now it prints what type we are trying to
add to what type of partitioning.
10.5 part: test cases and comments.
The code is in the merge commit 74fe1c44aa
When f.ex. table is partitioned by HASH(a) and we rename column `a' to
`b' partitioning filter stays unchanged: HASH(a). That's the wrong
behavior.
The patch updates partitioning filter in accordance to the new columns
names. That includes partition/subpartition expression and
partition/subpartition field list.
During rebuild of partition, the partitioning engine calls
alter_close_table(), which does not unlock and close some table
instances of the target table.
Then, the engine fails to rename partitions because there are table
instances that are still locked.
Closing all the table instance of the target table fixes the bug.
During rebuild of partition, the partitioning engine calls
alter_close_table(), which does not unlock and close some table
instances of the target table.
Then, the engine fails to rename partitions because there are table
instances that are still locked.
Closing all the table instance of the target table fixes the bug.
:: Syntax change ::
Keyword AUTO enables history partition auto-creation.
Examples:
CREATE TABLE t1 (x int) WITH SYSTEM VERSIONING
PARTITION BY SYSTEM_TIME INTERVAL 1 HOUR AUTO;
CREATE TABLE t1 (x int) WITH SYSTEM VERSIONING
PARTITION BY SYSTEM_TIME INTERVAL 1 MONTH
STARTS '2021-01-01 00:00:00' AUTO PARTITIONS 12;
CREATE TABLE t1 (x int) WITH SYSTEM VERSIONING
PARTITION BY SYSTEM_TIME LIMIT 1000 AUTO;
Or with explicit partitions:
CREATE TABLE t1 (x int) WITH SYSTEM VERSIONING
PARTITION BY SYSTEM_TIME INTERVAL 1 HOUR AUTO
(PARTITION p0 HISTORY, PARTITION pn CURRENT);
To disable or enable auto-creation one can use ALTER TABLE by adding
or removing AUTO from partitioning specification:
CREATE TABLE t1 (x int) WITH SYSTEM VERSIONING
PARTITION BY SYSTEM_TIME INTERVAL 1 HOUR AUTO;
# Disables auto-creation:
ALTER TABLE t1 PARTITION BY SYSTEM_TIME INTERVAL 1 HOUR;
# Enables auto-creation:
ALTER TABLE t1 PARTITION BY SYSTEM_TIME INTERVAL 1 HOUR AUTO;
If the rest of partitioning specification is identical to CREATE TABLE
no repartitioning will be done (for details see MDEV-27328).
:: Description ::
Before executing history-generating DML command (see the list of commands below)
add N history partitions, so that N would be sufficient for potentially
generated history. N > 1 may be required when history partitions are switched
by INTERVAL and current_timestamp is N times further than the interval
boundary of the last history partition.
If the last history partition equals or exceeds LIMIT records then new history
partition is created and selected as the working partition. According to
MDEV-28411 partitions cannot be switched (or created) while the command is
running. Thus LIMIT does not carry strict limitation and the history partition
size must be planned as LIMIT value plus average number of history one DML
command can generate.
Auto-creation is implemented by synchronous fast_alter_partition_table() call
from the thread of the executed DML command before the command itself is run
(by the fallback and retry mechanism similar to Discovery feature,
see Open_table_context).
The name for newly added partitions are generated like default partition names
with extension of MDEV-22155 (which avoids name clashes by extending assignment
counter to next free-enough gap).
These DML commands can trigger auto-creation:
DELETE (including multitable DELETE, excluding DELETE HISTORY)
UPDATE (including multitable UPDATE)
REPLACE (including REPLACE .. SELECT)
INSERT .. ON DUPLICATE KEY UPDATE (including INSERT .. SELECT .. ODKU)
LOAD DATA .. REPLACE
:: Bug fixes ::
MDEV-23642 Locking timeout caused by auto-creation affects original DML
The reasons for this are:
- Do not disrupt main business process (the history is auxiliary service);
- Consequences are non-fatal (history is not lost, but comes into wrong
partition; fixed by partitioning rebuild);
- There is more freedom for application to fail in this case or not: it may
read warning info and find corresponding error number.
- While non-failing command is easy to handle by an application and fail it,
the opposite is hard to handle: there is no automatic actions to fix
failed command and retry, DBA intervention is required and until then
application is non-functioning.
MDEV-23639 Auto-create does not work under LOCK TABLES or inside triggers
Don't do tdc_remove_table() for OT_ADD_HISTORY_PARTITION because it is
not possible in locked tables mode.
LTM_LOCK_TABLES mode (and LTM_PRELOCKED_UNDER_LOCK_TABLES) works out
of the box as fast_alter_partition_table() can reopen tables via
locked_tables_list.
In LTM_PRELOCKED we reopen and relock table manually.
:: More fixes ::
* some_table_marked_for_reopen flag fix
some_table_marked_for_reopen affets only reopen of
m_locked_tables. I.e. Locked_tables_list::reopen_tables() reopens only
tables from m_locked_tables.
* Unused can_recover_from_failed_open() condition
Is recover_from_failed_open() can be really used after
open_and_process_routine()?
:: Reviewed by ::
Sergei Golubchik <serg@mariadb.org>
When we need to add/remove or change LIMIT, INTERVAL, AUTO we have to
recreate partitioning from scratch (via data copy). Such operations
should be done fast. To remove options like LIMIT or INTERVAL one
should write:
alter table t1 partition by system_time;
The command checks whether it is new or existing SYSTEM_TIME
partitioning. And in the case of new it behaves as CREATE would do:
adds default number of partitions (2). If SYSTEM_TIME partitioning
already existed it just changes its options: removes unspecified ones
and adds/changes those specified explicitly. In case when partitions
list was supplied it behaves as usual: does full repartitioning.
Examples:
create or replace table t1 (x int) with system versioning
partition by system_time limit 100 partitions 4;
# Change LIMIT
alter table t1 partition by system_time limit 33;
# Remove LIMIT
alter table t1 partition by system_time;
# This does full repartitioning
alter table t1 partition by system_time limit 33 partitions 4;
# This does data copy as pruning will require records in correct partitions
alter table t1 partition by system_time interval 1 hour
starts '2000-01-01 00:00:00';
# But this works fast, LIMIT will apply to DML commands
alter table t1 partition by system_time limit 33;
To sum up, ALTER for SYSTEM_TIME partitioning does full repartitioning
when:
- INTERVAL was added or changed;
- partition list or partition number was specified;
Otherwise it does fast alter table.
Cleaned up dead condition in set_up_default_partitions().
Reviewed by:
Oleksandr Byelkin <sanja@mariadb.com>
Nikita Malyavin <nikitamalyavin@gmail.com>
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.
Make it possible to specify engine-defined attributes on partitions
as well as tables.
If an engine-defined attribute is only specified at the table level,
it applies to all the partitions in the table.
This is a backward-compatible behavior.
If the same attribute is specified both at the table level and the
partition level, the per-partition one takes precedence.
So, we can consider per-table attributes as default values.
One cannot specify engine-defined attributes on subpartitions.
Implementation details:
* We store per-partition attributes in the partition_element class
because we already have the part_comment field, which is for
per-partition comments.
* In the case of ALTER TABLE statements, the partition_elements in
table->part_info is set up by mysql_unpack_partition().
So, we parse per-partition attributes after the call of the function.
Syntax for CONVERT TABLE
ALTER TABLE tbl_name CONVERT TABLE tbl_name TO PARTITION partition_name partition_spec
Examples:
ALTER TABLE t1 CONVERT TABLE tp2 TO PARTITION p2 VALUES LESS THAN MAX_VALUE();
New ALTER_PARTITION_CONVERT_IN command for
fast_alter_partition_table() is done in alter_partition_convert_in()
function which basically does ha_rename_table().
Table structure and data check is basically the same as in EXCHANGE
PARTITION command. And these are done by
compare_table_with_partition() and check_table_data().
Atomic DDL is done by the scheme from MDEV-22166 (see the
corresponding commit message). The only differnce is that it also has
to drop source table frm and that is done by WFRM_DROP_CONVERTED_FROM.
Initial patch was done by Dmitry Shulga <dmitry.shulga@mariadb.com>
Syntax for CONVERT keyword
ALTER TABLE tbl_name
[alter_option [, alter_option] ...] |
[partition_options]
partition_option: {
...
| CONVERT PARTITION partition_name TO TABLE tbl_name
}
Examples:
ALTER TABLE t1 CONVERT PARTITION p2 TO TABLE tp2;
New ALTER_PARTITION_CONVERT_OUT command for
fast_alter_partition_table() is done in alter_partition_convert_out()
function which basically does ha_rename_table().
Partition to extract is marked with the same flag as dropped
partition: PART_TO_BE_DROPPED. Note that we cannot have multiple
partitioning commands in one ALTER.
For DDL logging basically the principle is the same as for other
fast_alter_partition_table() commands. The only difference is that it
integrates late Atomic DDL functions and introduces additional phase
of WFRM_BACKUP_ORIGINAL. That is required for binlog consistency
because otherwise we could not revert back after WFRM_INSTALL_SHADOW
is done. And before DDL log is complete if we crash or fail the
altered table will be already new but binlog will miss that ALTER
command. Note that this is different from all other atomic DDL in that
it rolls back until the ddl_log_complete() is done even if everything
was done fully before the crash.
Test cases added to:
parts.alter_table \
parts.partition_debug \
versioning.partition \
atomic.alter_partition
Dead code cleanup:
part_info->num_parts usage was wrong and working incorrectly in
mysql_drop_partitions() because num_parts is already updated in
prep_alter_part_table(). We don't have to update part_info->partitions
because part_info is destroyed at alter_partition_lock_handling().
Cleanups:
- DBUG_EVALUATE_IF() macro replaced by shorter form DBUG_IF();
- Typo in ER_KEY_COLUMN_DOES_NOT_EXITS.
Refactorings:
- Splitted write_log_replace_delete_frm() into write_log_delete_frm()
and write_log_replace_frm();
- partition_info via DDL_LOG_STATE;
- set_part_info_exec_log_entry() removed.
DBUG_EVALUATE removed
DBUG_EVALUTATE was only added for consistency together with
DBUG_EVALUATE_IF. It is not used anywhere in the code.
DBUG_SUICIDE() fix on release build
On release DBUG_SUICIDE() was statement. It was wrong as
DBUG_SUICIDE() is used in expression context.
- DISCARD/IMPORT TABLESPACE are the only tablespace commands left
- TABLESPACE arguments for CREATE TABLE and ALTER ... ADD PARTITION are
ignored.
- Tablespace names are not shown anymore in .frm and not shown in
information schema
Other things
- Removed end spaces from sql/CMakeList.txt
in about a hundred of users of MY_BITMAP, only two were using its
built-in mutex, and only one of those two was actually needing it.
Remove the mutex from MY_BITMAP, remove all associated conditions
and checks in bitmap functions. Use an external LOCK_temp_pool
mutex and temp_pool_set_next/temp_pool_clear_bit acccessors.
Remove bitmap_init/bitmap_free, always use my_* versions.
