dict_create_foreign_constraints_low(): Tolerate the keywords
IGNORE and ONLINE between the keywords ALTER and TABLE.
We should really remove the hacky FOREIGN KEY constraint parser
from InnoDB.
dict_create_foreign_constraints_low(): Clean up the way in
which the error messages are initialized, and ensure that
the table name is always initialized.
The code path where the table was not being rebuilt during ALTER TABLE
was not covered by the test. Add coverage, and remove the debug assertion
that could fail in this case.
ha_innobase::commit_inplace_alter_table(): Do not crash if
innobase_update_foreign_cache() returns an error. It can return
an error on ALTER TABLE if an inconsistent FOREIGN KEY constraint
was created earlier when SET foreign_key_checks=0 was in effect.
Instead, report a warning to the client that constraints cannot
be loaded.
In RENAME TABLE, when an error occurs while renaming FOREIGN KEY
constraint, that error would be overwritten when renaming the
InnoDB internal tables related to FULLTEXT INDEX.
row_rename_table_for_mysql(): Do not attempt to rename the internal
tables if an error already occurred.
This problem was originally reported as Oracle Bug#27545888.
row_ins_check_foreign_constraint(): Do not overwrite hard errors
with the soft error DB_LOCK_WAIT. This prevents an infinite
wait loop when DB_INTERRUPTED was returned. For DB_LOCK_WAIT,
row_insert_for_mysql() would keep invoking row_ins_step() and the
transaction would remain active until the server shutdown is initiated.
table_already_fk_prelocked() was looking for a table in the wrong
list (not the complete list of prelocked tables, but only in its tail,
starting from the current table - which is always empty for the last
added table), so for circular FKs it kept adding same tables to the list
indefinitely.
Backport of d6d7e169fb
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
row_ins_check_foreign_constraint(): On timeout,
return DB_LOCK_WAIT_TIMEOUT instead of DB_LOCK_WAIT,
so that the lock wait will be properly terminated.
Also, replace some redundant assignments.
It looks like this bug was introduced in MySQL 5.7.8 by:
commit a97f6b91227c7e0fc3151cfe5421891e79c12d19
Author: Annamalai Gurusami <annamalai.gurusami@oracle.com>
Date: Tue Jun 9 16:02:31 2015 +0530
Bug #20953265 INNODB: FAILING ASSERTION: RESULT != FTS_INVALID
MDEV-13498 is a performance regression that was introduced in MariaDB 10.2.2
by commit fec844aca8
which introduced some Galera-specific conditions that were being
evaluated even if the write-set replication was not enabled.
MDEV-13246 Stale rows despite ON DELETE CASCADE constraint
is a correctness regression that was introduced by the same commit.
Especially the subcondition
!(parent && que_node_get_type(parent) == QUE_NODE_UPDATE)
which is equivalent to
!parent || que_node_get_type(parent) != QUE_NODE_UPDATE
makes little sense. If parent==NULL, the evaluation would proceed to the
std::find() expression, which would dereference parent. Because no SIGSEGV
was observed related to this, we can conclude that parent!=NULL always
holds. But then, the condition would be equivalent to
que_node_get_type(parent) != QUE_NODE_UPDATE
which would not make sense either, because the std::find() expression
is actually assuming the opposite when casting parent to upd_node_t*.
It looks like this condition never worked properly, or that
it was never properly tested, or both.
wsrep_must_process_fk(): Helper function to check if FOREIGN KEY
constraints need to be processed. Only evaluate the costly std::find()
expression when write-set replication is enabled.
Also, rely on operator<<(std::ostream&, const id_name_t&) and
operator<<(std::ostream&, const table_name_t&) for pretty-printing
index and table names.
row_upd_sec_index_entry(): Add !wsrep_thd_is_BF() to the condition.
This is applying part of "Galera MW-369 FK fixes"
f37b79c6da
that is described by the following part of the commit comment:
additionally: skipping wsrep_row_upd_check_foreign_constraint if thd has
BF, essentially is applier or replaying
This FK check would be needed only for populating parent row FK keys
in write set, so no use for appliers
table_already_fk_prelocked() was looking for a table in the wrong
list (not the complete list of prelocked tables, but only in its tail,
starting from the current table - which is always empty for the last
added table), so for circular FKs it kept adding same tables to the list
indefinitely.
Problem :
---------
Information_Schema.referential_constraints (UNIQUE_CONSTRAINT_NAME)
shows NULL for a foreign key constraint after restarting the server.
If any dml or query (select/insert/update/delete) is done on
referenced table, then the constraint name is correctly shown.
Solution :
----------
UNIQUE_CONSTRAINT_NAME column is the key name of the referenced table.
In innodb, FK reference is stored as a list of columns in referenced
table in INNODB_SYS_FOREIGN and INNODB_SYS_FOREIGN_COLS. The referenced
column must have at least one index/key with the referenced column as
prefix but the key name itself is not included in FK metadata. For this
reason, the UNIQUE_CONSTRAINT_NAME is only filled up when the
referenced table is actually loaded in innodb dictionary cache.
The information_schema view calls handler::get_foreign_key_list() on
foreign key table to read the FK metadata. The UNIQUE_CONSTRAINT_NAME
information shows NULL based on whether the referenced table is
already loaded or not.
One way to fix this issue is to load the referenced table while reading
the FK metadata information, if needed.
Reviewed-by: Sunny Bains <sunny.bains@oracle.com>
RB: 14654
