deadlock was encountered
The bug is caused by an inconsistent handling of the IGNORE
clause. A read from a const table caused a lock timeout
(ER_LOCK_TIMEOUT) in innodb. Since the IGNORE clause was
given, the timeout was converted into a warning instead of
an error, thus not populating the diagnostics area. When
innodb subsequently marked the transaction for rollback,
mysql asserted since the diag.area was empty.
This patch consists of only a test case, as the bug itself
was fixed by the patch for Bug #46539
Bug#41756 "Strange error messages about locks from InnoDB".
In JT_EQ_REF (join_read_key()) access method,
don't try to unlock rows in the handler, unless certain that
a) they were locked
b) they are not used.
Unlocking of rows is done by the logic of the nested join loop,
and is unaware of the possible caching that the access method may
have. This could lead to double unlocking, when a row
was unlocked first after reading into the cache, and then
when taken from cache, as well as to unlocking of rows which
were actually used (but taken from cache).
Delegate part of the unlocking logic to the access method,
and in JT_EQ_REF count how many times a record was actually
used in the join. Unlock it only if it's usage count is 0.
Implemented review comments.
mysql-test/r/innodb_lock_wait_timeout_1.result:
Update results (Bug41756).
mysql-test/t/innodb_lock_wait_timeout_1.test:
Add a test case (Bug#41756).
sql/item_subselect.cc:
Complete struct READ_RECORD initialization with a new
member to unlock records.
sql/records.cc:
Extend READ_RECORD API with a method to unlock read records.
sql/sql_select.cc:
In JT_EQ_REF (join_read_key()) access method,
don't try to unlock rows in the handler, unless certain that
a) they were locked
b) they are not used.
sql/sql_select.h:
Add members to TABLE_REF to count TABLE_REF buffer usage count.
sql/structs.h:
Update declarations.
Bug#46539 Various crashes on INSERT IGNORE SELECT + SELECT FOR UPDATE.
If a transaction was rolled back inside InnoDB due to a deadlock
or lock wait timeout, and the statement had IGNORE clause,
the server could crash at the end of the statement or on shutdown.
This was caused by the error handling infrastructure's attempt to
ignore a non-ignorable error.
When a transaction rollback request is raised, switch off
current_select->no_error flag, so that the following error
won't be ignored.
Instead, we could add !thd->is_fatal_sub_stmt_error to
my_message_sql(), but since in write_record() we switch
off no_error, the same approach is used in
thd_mark_transaction_to_rollback().
@todo: call thd_mark_transaction_to_rollback() from
handler::print_error(), then we can easily make sure
that the error reported by print_error is not ignored.
mysql-test/r/innodb_lock_wait_timeout_1.result:
Update results (Bug#46539).
mysql-test/t/innodb_lock_wait_timeout_1.test:
Add a test case for Bug#46539
sql/sql_class.cc:
When a transaction rollback request is raised, switch of
current_select->no_error flag, so that the following error
won't be ignored.
2009-10-28 17:49:56 +03:00
Renamed from mysql-test/r/bug40113.result (Browse further)
