Don't allow the referencing key column from NULL TO NOT NULL
when
1) Foreign key constraint type is ON UPDATE SET NULL
2) Foreign key constraint type is ON DELETE SET NULL
3) Foreign key constraint type is UPDATE CASCADE and referenced
column declared as NULL
Don't allow the referenced key column from NOT NULL to NULL
when foreign key constraint type is UPDATE CASCADE
and referencing key columns doesn't allow NULL values
get_foreign_key_info(): InnoDB sends the information about
nullability of the foreign key fields and referenced key fields.
fk_check_column_changes(): Enforce the above rules for COPY
algorithm
innobase_check_foreign_drop_col(): Checks whether the dropped
column exists in existing foreign key relation
innobase_check_foreign_low() : Enforce the above rules for
INPLACE algorithm
dict_foreign_t::check_fk_constraint_valid(): This is used
by CREATE TABLE statement to check nullability for foreign
key relation.
trx_t::commit_in_memory(): Empty the detailed_error string, so that
FOREIGN KEY error messages from an earlier transaction will not be
wrongly reused in ha_innobase::get_error_message().
Reviewed by: Thirunarayanan Balathandayuthapani
- When foreign_key_check is disabled, allowing to modify the
column which is part of foreign key constraint can lead to
refusal of TRUNCATE TABLE, OPTIMIZE TABLE later. So it make
sense to block the column modify operation when foreign key
is involved irrespective of foreign_key_check variable.
Correct way to modify the charset of the column when fk is involved:
SET foreign_key_checks=OFF;
ALTER TABLE child DROP FOREIGN KEY fk, MODIFY m VARCHAR(200) CHARSET utf8mb4;
ALTER TABLE parent MODIFY m VARCHAR(200) CHARSET utf8mb4;
ALTER TABLE child ADD CONSTRAINT FOREIGN KEY (m) REFERENCES PARENT(m);
SET foreign_key_checks=ON;
fk_check_column_changes(): Remove the FOREIGN_KEY_CHECKS while
checking the column change for foreign key constraint. This
is the partial revert of commit 5f1f2fc0e4
and it changes the behaviour of copy alter algorithm
ha_innobase::prepare_inplace_alter_table(): Find the modified
column and check whether it is part of existing and newly
added foreign key constraint.
ha_innobase::referenced_by_foreign_key(): Protect the check with
dict_sys.freeze(), to prevent races with TRUNCATE TABLE.
The test innodb.instant_alter_crash has been adjusted for this
additional locking.
dict_table_is_referenced_by_foreign_key(): Removed (merged to
the only caller).
create_table_info_t::create_table(): Ignore missing indexes for
FOREIGN KEY constraints if foreign_key_checks=0.
create_table_info_t::create_table_update_dict(): Rewritten as
a static function. Do not return any error.
ha_innobase::create(): When trx!=nullptr and we are operating
on a persistent table, do not rollback, commit, or release the
data dictionary latch.
ha_innobase::truncate(): Protect the entire critical section
with an exclusive dict_sys.latch, so that
ha_innobase::referenced_by_foreign_key() on referenced tables
will return a consistent result. In case of a failure,
invoke dict_load_foreigns() to restore also any FOREIGN KEY
constraints.
ha_innobase::free_foreign_key_create_info(): Define inline.
lock_release(): Disregard innodb_evict_tables_on_commit_debug=ON
when dict_sys.locked() holds. It would hold when fts_load_stopword()
is invoked by create_table_info_t::create_table_update_dict().
dict_sys_t::locked(): Return whether the current thread is holding
the exclusive dict_sys.latch.
dict_sys_t::frozen_not_locked(): Return whether any thread is
holding a shared dict_sys.latch.
In the test main.mysql_upgrade, the InnoDB persistent statistics
will no longer be recalculated in ha_innobase::open() as part of
CHECK TABLE ... FOR UPGRADE. They were deleted earlier in the test.
Tested by: Matthias Leich
This essentially reverts commit 4e89ec6692
and only disables InnoDB persistent statistics for tests where it is
desirable. By design, InnoDB persistent statistics will not be updated
except by ANALYZE TABLE or by STATS_AUTO_RECALC.
The internal transactions that update persistent InnoDB statistics
in background tasks (with innodb_stats_auto_recalc=ON) may cause
nondeterministic query plans or interfere with some tests that deal
with other InnoDB internals, such as the purge of transaction history.
This patch changes the main name of 3 byte character set from utf8 to
utf8mb3. New old_mode UTF8_IS_UTF8MB3 is added and set TRUE by default,
so that utf8 would mean utf8mb3. If not set, utf8 would mean utf8mb4.
This feature adds the functionality of ignorability for indexes.
Indexes are not ignored be default.
To control index ignorability explicitly for a new index,
use IGNORE or NOT IGNORE as part of the index definition for
CREATE TABLE, CREATE INDEX, or ALTER TABLE.
Primary keys (explicit or implicit) cannot be made ignorable.
The table INFORMATION_SCHEMA.STATISTICS get a new column named IGNORED that
would store whether an index needs to be ignored or not.
In btr_index_rec_validate(), externally stored column
check is missing while matching the length of the field
with the length of the field data stored in record.
Fetch the length of the externally stored part and compare it
with the fixed field length.
* be strict in CREATE TABLE, just like in ALTER TABLE, because
CREATE TABLE, just like ALTER TABLE, can be rolled back for any engine
* but don't auto-convert warnings into errors for engine warnings
(handler::create) - this matches ALTER TABLE behavior
* and not when creating a default record, these errors are handled
specially (and replaced with ER_INVALID_DEFAULT)
* always issue a Note when a non-unique key is truncated, because it's
not a Warning that can be converted to an Error. Before this commit
it was a Note for blobs and a Warning for all other data types.
Problem:
=======
InnoDB drops the column which has foreign key relations on it. So it
tries to load the foreign key during rename process of copy algorithm
even though the foreign_key_check is disabled.
Solution:
========
During alter copy algorithm, InnoDB ignores the error while loading
the foreign key constraint if foreign key check is disabled. It
should throw the warning about failure of the foreign key constraint
when foreign key check is disabled.
- IF EXISTS ends with a list of all not existing object, instead of a
separate note for every not existing object
- Produce a "Note" for all wrongly dropped objects
(like trying to do DROP SEQUENCE for a normal table)
- Do not write existing tables that could not be dropped to binlog
Other things:
MDEV-22820 Bogus "Unknown table" warnings produced upon attempt to drop
parent table referenced by FK
This was caused by an older version of this commit patch and later fixed
Remove usage of deprecated variable storage_engine. It was deprecated in 5.5 but
it never issued a deprecation warning. Make it issue a warning in 10.5.1.
Replaced with default_storage_engine.
Parenthesis around table names and derived tables should be allowed
in FROM clauses and some other context as it was in earlier versions.
Returned test queries that used such parenthesis in 10.3 to their
original form. Adjusted test results accordingly.
Rather than add a small extra amount on the size of chunks, keep it
of the specified size. The rest of the chunk initialization code
adapts to this small size reduction. This has been made in the general
case, not just large pages, to keep it simple.
The chunks size is controlled by innodb-buffer-pool-chunk-size. In the
code increasing this by a descriptor table size length makes it
difficult with large pages. With innodb-buffer-pool-chunk-size set to 2M
the code before this commit would of added a small amount extra to this
value when it tried to allocate this. While not normally a problem it is
with large pages, it now requires addition space, a whole extra large
page. With a number of pools, or with 1G or 16G large pages this is
quite significant.
By removing this additional amount, DBAs can set
innodb-buffer-pool-chunk size to the large page size, or a multiple of
it, and actually get that amount allocated. Previously they had to fudge
a value less.
The innodb.test results show how this is fudged over a number of tests. With
this change the values are just between 488 and 500 depending on architecture
and build options.
Tested with --large-pages --innodb-buffer-pool-size=256M
--innodb-buffer-pool-chunk-size=2M on x86_64 with 2M default large page
size. Breaking before buf_pool init, one large page was allocated in
MyISAM, by the end of the function 128 huge pages where allocated as
expected. A further 16 pages where allocated for a 32M log buffer and
during startup 1 page was allocated briefly to the redo log.
InnoDB takes a lot of time to perform null updates. The reason is that
even though an empty update vector was created, InnoDB will go on to
write undo log records and update the system columns
DB_TRX_ID and DB_ROLL_PTR in the clustered index, and of course write
redo log for all this.
This could have been fixed properly in
commit 54a492ecac more than 10 years ago.
MDEV-14222 Unnecessary 'cascade' memory allocation for every updated row
when there is no FOREIGN KEY
This reverts the MySQL 5.7.2 change
377774689b
which introduced these problems. MariaDB 10.2.2 inherited these problems
in commit 2e814d4702.
The FOREIGN KEY CASCADE and SET NULL operations implemented as
procedural recursion are consuming more than 8 kilobytes of stack
(9 stack frames) per iteration in a non-debug GNU/Linux AMD64 build.
This is why we need to limit the maximum recursion depth to 15 steps
instead of the 255 that it used to be in MySQL 5.7 and MariaDB 10.2.
A corresponding change was made in MySQL 5.7.21 in
7b26dc98a6
InnoDB limited the maximum number of bytes per character to 4.
But, the filename character set that was introduced in MySQL 5.1
uses up to 5 bytes per character.
To allow InnoDB tables to be created with wider characters, let
us split the mbminmaxlen fields into mbminlen, mbmaxlen, and increase
the limit to 7 bytes per character. This will increase the payload size
of dtype_t and dict_col_t by one bit. The storage size will be unchanged
(54 bits and 77 bits will use the same number of bytes as the
previous sizes 53 and 76 bits).
