MySQL 8.0 Release Notes
This release is no longer available for download. It was removed due to a critical issue that could stop the server from restarting following the creation of a very large number of tables (8001 or more). Please upgrade to MySQL 8.0.39 instead.
Audit log pruning did not function after removing or renaming a file from the audit log. Now pruning continues in such cases, but with a warning printed in the error log stating that it was not possible to delete the missing audit log file. (Bug #35902913)
Upgraded the bundled googletest
and
googlemock
sources to version 1.14.0.
(Bug #36562482)
Added a missing dependency on GenError
.
(Bug #36551721)
It is now possible on Linux systems to build MySQL using a
bundled tcmalloc
library that is provided
with the source by specifying
-DWITH_TCMALLOC=BUNDLED
. This is
supported on Linux only.
(Bug #36313839)
The bundled tcmalloc()
is now used when
building MySQL on Enterprise Linux 8.
(Bug #114844, Bug #35674008)
Linux aarch64
platform binaries are now built
using patchelf
--page-size=65536
for compatibility with
systems using either 4k or 64k for the page size.
(Bug #114233, Bug #36393794)
The conn_delay/Waiting in connection_control
plugin
stage was not reset after a delay introduced by
the connection control plugin which resulted in incorrect
monitoring information.
(Bug #35205358)
Attempting to upgrade a MyISAM
table containing a mix of regular columns and generated columns
from MySQL 5.7 to 8.0 or later led to table corruption.
(Bug #105301, Bug #33503328)
Under certain conditions, a race condition could result in the
amount of RAM used by TABLE_HANDLES
increasing to a maximum of 9GB.
(Bug #36170903)
The PROCESSLIST_INFO
column of
THREADS
was not updated when
executing a prepared statement.
Thanks to Daniel Lenski and Amazon for the contribution. (Bug #104121, Bug #33057164)
The deprecation warning issued when authenticating with the
mysql_native_password
plugin is now issued
only once.
(Bug #35792948)
Connecting to a thread group that had no connection handler threads stalled. We fix this by making sure that connection handler threads terminate only if there is at least one connection thread left. (Bug #36550125)
InnoDB:
MySQL unexpectedly halted on an
UPDATE
after an
ALTER TABLE
operation.
(Bug #36571091)
References: This issue is a regression of: Bug #35183686.
InnoDB: The log index size calculation now accounts for column order changes. (Bug #36526369)
References: This issue is a regression of: Bug #35183686.
InnoDB:
File system operations performed by InnoDB
now consistently fsync
the parent directory
when performing directory altering tasks.
(Bug #36174938)
InnoDB:
In debug builds, setting the
innodb_interpreter_output
debug variable
would cause the server to unexpectedly halt. This is now a
read-only variable.
(Bug #36041032)
InnoDB:
For tables created with an index on a column that was too wide
for the redundant row format (allowed before MySQL 5.7.35), an
in-place upgrade silently imported the table but it was not
accessible, which interfered with making backups. Now all
operations that involve using the invalid index are rejected
with ER_INDEX_CORRUPT
until the
index is dropped. An
ER_IB_INDEX_PART_TOO_LONG
error
is also reported in the error log.
(Bug #35869747)
References: See also: Bug #34826861.
InnoDB:
An InnoDB
assertion error referencing an
invalid column index was triggered when the column index was
valid.
(Bug #34800754)
InnoDB:
With an empty
XA
transaction, shutting the server down after an XA
START
would cause the server to halt unexpectedly.
(Bug #32416819)
InnoDB: Shutting down the replication applier or binlog applier while processing an empty XA transaction caused the system to unexpectedly halt. (Bug #32416819)
InnoDB:
Removed unnecessary heap usage in the
Validate_files::check()
function.
Our thanks to Huaxiong Song for the contribution. (Bug #115041, Bug #36626203)
InnoDB:
If a partition table was read with
innodb_parallel_read_threads=1
,
read performance greatly decreased from any table after 256
reads. InnoDB behaved as if it reached the maximum capacity of
parallel read threads despite not using any.
Our thanks to Ke Yu for the contribution. (Bug #114154, Bug #36347408)
InnoDB:
The result from a spatial index containing a column with a
spatial reference identifier (SRID) attribute was empty. In
addition, using FORCE INDEX
to force a
covering index scan on a spatial index led to an assertion.
(Bug #112676, Bug #114200, Bug #35894664, Bug #36361834)
InnoDB:
Fixed performance issues related to querying the
data_lock
and
data_lock_waits
tables when thousands of
read-only transactions were present.
(Bug #109539, Bug #34951273)
Replication:
If a source contained a stored, generated column populated by a
JSON function and
binlog_row_image
was set to
MINIMAL
, any subsequent update or deletion on
the underlying column failed with the following error:
Invalid JSON text in argument 1 to function json_extract: 'The document is empty.'
The replica attempted to re-evaluate the generated column and failed with that error because the underlying column was unavailable. As of this release, stored, generated columns are not re-evaluated when the underlying columns are unavailable. (Bug #36515172)
Replication:
When running GTID-based replication with
relay_log_space_limit
enabled,
a restart of the auto positioning protocol sometimes resulted in
an infinite loop, leading to a deadlock in replication. This was
because relay_log_space_limit
was not
honored, not only for transactions whose size exceed this limit,
but when the replica could not purge previous logs as well.
To fix this issue, we make the following changes:
The receiver respects
relay_log_space_limit
as set by the user,
unless a transaction received by the receiver cannot fit
into the purged relay log. Before queuing the received
transaction, receiver now checks whether scheduling a full
transaction is possible. If not, the receiver performs the
following actions:
Sets the flag indicating that receiver is waiting
Rotates the relay log
Waits until it is notified that relay log purge was executed and that the applier has purged all available relay logs; after this, the receiver may queue a transaction without checking the limit again
Before moving to the next file, the coordinator checks whether the receiver is waiting for available relay log space. If so, the coordinator forcibly purges the applied logs, including the current relay log file. To purge the current relay log file safely, the coordinator must do the following:
Synchronize all of its workers before moving to the next file
Forcibly update group positions, which is necessary to allow current purging of the relay log
Update the variable read by the receiver which contains relay log filename to which applier was moved
These operations are allowed because we know that receiver waits at a transaction boundary and rotates the relay log before waiting.
(Bug #36507020)
Replication:
Worker jobs now contain information about the relay log file
which initiated the transaction, instead of using the default
defined by relay_log
.
(Bug #36395631)
Replication: Handling an incident while transactions were being committed to the binary log caused MySQL to wait indefinitely. (Bug #35671897)
Group Replication:
Removed a memory leak from
/xcom/gcs_xcom_networking.cc
.
(Bug #36532199)
Group Replication: Under certain circumstances, if a primary's host experienced network inactivity of 20 seconds or more, the secondaries could stop unexpectedly. (Bug #36306144)
Group Replication: Under certain circumstances, if garbage collection occurred just before a relay log rotation, it could cause the applier to stop applying new transactions on the secondary members.
This was caused by garbage collection incrementing the relay
log's last_committed
and
sequence_number
, creating a gap in the
recorded sequence_number
after the log
rotation. The applier was unaffected if the gap occurred
anywhere else in the relay log.
As of this release, only last_committed
is
updated during garbage collection.
(Bug #36280130, Bug #36446250)
JSON:
Added missing checks for error handling to
NULLIF()
,
COALESCE()
, and the shift
(>>
)
operator.
(Bug #113668, Bug #35513196, Bug #36198403)
References: See also: Bug #31358416.
MySQL NDB ClusterJ: Running the ClusterJ test suite resulted in an error message saying a number of threads did not exist. That was due to some wrong handling of threads and connections, which was corrected by this patch. (Bug #36086735)
Averages of certain numbers were not always computed correctly. (Bug #36563773)
The following files in strings
contained
incorrect license information:
mb_wc.h
ctype-uca.cc
ctype-ucs2.cc
ctype-utf8.cc
dtoa.cc
strxmov.cc
strxnmov.cc
(Bug #36506181)
In certain unusual cases, the
UpdateXML()
function did not
process all of its arguments correctly.
(Bug #36479091)
Explaining a query which used FORCE INDEX
on
a spatial index containing a column with SRID attributes led to
an unplanned exit.
(Bug #36418426)
When incrementing the reference count for an expression,
underlying expressions within this expression are not looked at.
While removing an expression, after decrementing the reference
count, even the underlying expressions were examined, which led
to unintentional deletion of the underlying expressions. This
issue manifested in Item_ref::real_item()
as
well as in an assert in sql/item.h
. We fix
this by not looking at the underlying expression unless the
current expression contains the only remaining reference.
(Bug #36204344, Bug #36356279)
Under certain conditions,
EXPLAIN FORMAT=JSON FOR
CONNECTION
sometimes led to an unplanned exit.
(Bug #36189820)
Some CREATE USER
statements were
not handled correctly.
(Bug #36022885)
For a SELECT
with ORDER
BY
and LIMIT
, the optimizer first
chose a full table scan with a very expensive cost, then
performed another check and used the
perform_order_index
type of path, but this
was not reflected by the cost in the optimizer plan.
(Bug #35930969)
Client connections were not alway terminated correctly during shutdown. (Bug #35854919)
All internal ACL bitmask variables are now explicitly 32 bits
(uint32_t
).
(Bug #35507223)
It was not possible to add a functional index on
FIND_IN_SET()
.
(Bug #35352161)
Running two concurrent OPTIMIZE
TABLE
statements on the same table with fulltext
indexes and
innodb_optimize_fulltext_only
enabled sometimes caused the server to exit.
(Bug #34929814)
Removed a memory leak observed while running
authentication_kerberos
under Valgrind.
(Bug #34482788, Bug #36570929)
The
gen_range()
function as implemented by the (deprecated) data masking plugin
did not always return the correct result.
This issue affected the data masking plugin only, and did not affect the data masking component which supersedes it. (Bug #34163992)
Fixed an erroneous comment in
include/my_command.h
.
Our thanks to Sho Nakazono for the contribution. (Bug #114507, Bug #36455468)
It was possible for a deterministic stored function to return an
incorrect result when the function used JOIN
ON
inside the return
statement. If
the query needed to be reprepared due to a table metadata caused
by, for example, FLUSH
TABLES
between two executions, the
ON
clause was sometimes lost.
(Bug #114235, Bug #36379879)