THOUGH IT IS NOT.
The following error message is misleading because it claims
that the BLOB space is not counted.
"ERROR 1118 (42000): Row size too large. The maximum row size for
the used table type, not counting BLOBs, is 8126. You have to
change some columns to TEXT or BLOBs"
When the ROW_FORMAT=compact or ROW_FORMAT=REDUNDANT is used,
the BLOB prefix is stored inline along with the row. So
the above error message is changed as follows depending on
the row format used:
For ROW_FORMAT=COMPRESSED or ROW_FORMAT=DYNAMIC, the error
message is as follows:
"ERROR 42000: Row size too large (> 8126). Changing some
columns to TEXT or BLOB may help. In current row format,
BLOB prefix of 0 bytes is stored inline."
For ROW_FORMAT=COMPACT or ROW_FORMAT=REDUNDANT, the error
message is as follows:
"ERROR 42000: Row size too large (> 8126). Changing some
columns to TEXT or BLOB or using ROW_FORMAT=DYNAMIC or
ROW_FORMAT=COMPRESSED may help. In current row
format, BLOB prefix of 768 bytes is stored inline."
rb://1252 approved by Marko Makela
PAGE SPLIT
page_rec_get_nth_const(): Map nth==0 to the page infimum.
btr_compress(adjust=TRUE): Add a debug assertion for nth>0. The cursor
should never be positioned on the page infimum.
btr_index_page_validate(): Add test instrumentation for checking the
return values of page_rec_get_nth_const() during CHECK TABLE, and for
checking that the page directory slot 0 always contains only one
record, the predefined page infimum record.
page_cur_delete_rec(), page_delete_rec_list_end(): Add debug
assertions guarding against accessing the page slot 0.
page_copy_rec_list_start(): Clarify a comment about ret_pos==0.
rb:1248 approved by Jimmy Yang
ha_innodb::records_in_range(): Remove a debug assertion
that prohibits an open range (full table).
The patch by Jorgen Loland only removed the assertion from the
built-in InnoDB, not from the InnoDB Plugin.
The use of Thread_iterator did not work on windows (linking problems).
Solution: Change the interface between the thread_pool and the server
to only use simple free functions.
This patch is for 5.5 only (mimicks similar solution in 5.6)
ha_innobase::records_in_range(): Remove a debug assertion
that prohibits an open range (full table).
This assertion catches unnecessary calls to this method,
but such calls are not harming correctness.
Backport from mysql-5.6 the fix
(revision-id sunny.bains@oracle.com-20120315045831-20rgfa4cozxmz7kz)
Bug#13839886 - CRASH IN INNOBASE_NEXT_AUTOINC
The assertion introduce in the fix for Bug#13817703
is too strong, a negative number can be greater
than the column max value, when the column value is
a negative number.
rb://978 Approved by Jimmy Yang.
rb:1236 approved by Marko Makela
ENABLE AUDI PLUGIN WHEN DDL
OPERATION HAPPENING
PROBLEM: While unloading the plugin, state is
not checked before it is to be reaped.
This can lead to simultaneous free of
plugin memory by more than one thread.
Multiple deallocation leads to server
crash. In the present bug two threads
deallocate the alog_log plugin.
SOLUTION: A check is added to ensure that only
one thread is unloading the plugin.
NOTE: No mtr test is added as it requires
multiple threads to access critical
section. debug_sync cannot be used in
the current senario because we dont
have access to thread pointer in
some of the plugin functions. IMHO no
test case in the current time frame.
NUMBERS
If a system variable was declared as deprecated without mention of an
alternative, the message would look funny, e.g. for @@delayed_insert_limit:
Warning 1287 '@@delayed_insert_limit' is deprecated and
will be removed in MySQL .
The message was meant to display the version number, but it's not
possible to give one when declaring a system variable.
The fix does two things:
1) The definition of the message
ER_WARN_DEPRECATED_SYNTAX_NO_REPLACEMENT is changed so that it does
not display a version number. I.e. in English the message now reads:
Warning 1287 The syntax '@@delayed_insert_limit' is deprecated and
will be removed in a future version.
2) The message ER_WARN_DEPRECATED_SYNTAX_WITH_VER is discontinued in
favor of ER_WARN_DEPRECATED_SYNTAX for system variables. This change
was already done in versions 5.6 and above as part of wl#5265. This
part is simply back-ported from the worklog.
WARNING
This patch is for mysql-5.5 only,
to be null-merged to mysql-5.6 and mysql-trunk.
This is a partial rollback of the file io instrumentation,
removing the instrumentation for mysql_file_stat in the archive engine.
See the bug comments for details.
FAILED IN CHECK_LOCK_AND_ST
Problem:
--------
lock_tables() is supposed to invoke check_lock_and_start_stmt()
for TABLE_LIST which are directly used by top level statement.
TABLE_LIST->prelocking_placeholder is set only for TABLE_LIST
which are used indirectly by stored programs invoked by top
level statement. Hence check_lock_and_start_stmt() should have
TABLE_LIST->prelocking_placeholder==false always, but it is
observed that this assert fails.
The failure is found during RQG test rqg_signal_resignal.
Analysis:
---------
open_tables() invokes open_and_process_routines() where it
finds all the TABLE_LIST that belong to the routine and
adds it to thd->lex->query_tables. During this process if
the open_and_process_routines() fail for some reason,
we are supposed to chop-off all the TABLE_LIST found during
calls to open_and_process_routines(). But, in practice this
is not happening.
thd->lex->query_tables_own_last is supposed to point to a
node in thd->lex->query_tables, which would be a first
TABLE_LIST used indirectly by stored programs invoked by
top level statement. This is found to be not-set correctly
when we plan to chop-off TABLE_LIST's, when
open_and_process_routines() failed.
close_tables_for_reopen() does chop-off all the TABLE_LIST
added after thd->lex->query_table_own_last. This is invoked
upon error in open_and_process_routines(). This call would
not work as expected as thd->lex->query_tables_own_last
is not set, or is not set to correctly.
Further, when open_tables() restarts the process of finding
TABLE_LIST belonging to stored programs, and as the
thd->lex->query_tables_own_last points to in-correct node,
there is possibility of new iteration setting the
thd->lex->query_tables_own_last past some old nodes that
belong to stored programs, added earlier and not removed.
Later when open_tables() completes, lock_tables() ends up
invoking check_lock_and_start_stmt() for TABLE_LIST which
belong to stored programs, which is not expected behavior
and hence we hit the assert
TABLE_LIST->prelocking_placeholder==false.
Due to above behavior, if a user application tries to
execute a SQL statement which invokes some stored function
and if the lock grant on stored function fails due to a
deadlock, then mysqld crashes.
Fix:
----
open_tables() remembers save_query_tables_last which points
to thd-lex->query_tables_last before calls to
open_and_process_routines(). If there is no known
thd->lex->query_tables_own_last set, we are now setting
thd->lex->query_tables_own_last to save_query_tables_last.
This will make sure that the call to close_tables_for_reopen()
will chop-off the list correctly, in other words we now
remove all the nodes added to thd->lex->query_tables, by
previous calls to open_and_process_routines().
Further, it is found that the problem exists starting
from 5.5, due to a code refactoring effort related to
open_tables(). Hence, the fix will be pushed in 5.5, 5.6
and trunk.
Documentation for class Item_outer_ref was wrong:
(*ref) may point to Item_field as well
(see e.g. Item_outer_ref::fix_fields)
So this casting in get_store_key() was wrong:
(*(Item_ref**)((Item_ref*)keyuse->val)->ref)->ref_type()
HEURISTICS FOR COMPRESSED PAGE SIZE
The fix of Bug#12845774 was supposed to skip known-to-fail
btr_cur_optimistic_insert() calls. There was only one such call, in
btr_cur_pessimistic_update(). All other callers of
btr_cur_pessimistic_insert() would release and reacquire the B-tree
page latch before attempting the pessimistic insert. This would allow
other threads to restructure the B-tree, allowing (and requiring) the
insert to succeed as an optimistic (single-page) operation.
Failure to attempt an optimistic insert before a pessimistic one would
trigger an attempt to split an empty page.
rb:1234 approved by Sunny Bains
DURING SERVER STARTUP
The options parser now correctly checks for ambiguous prefixes in
enumerated variables and emits an error when the value supplied is
ambiguous.
No test added since mysql-test-run.pl can't handle server startup
failures as an expected state.
Additional patch to remove the part_id -> ref_buffer offset.
The partitioning id and the associate record buffer can
be found without having to calculate it.
By initializing it for each used partition, and then reuse
the key-buffer from the queue, it is not needed to have
such map.
Facebook got a case where the page compresses really well so that
btr_cur_optimistic_update() returns DB_UNDERFLOW, but when a record
gets updated, the compression rate radically changes so that
btr_cur_insert_if_possible() can not insert in place despite
reorganizing/recompressing the page, leading to the assertion failing.
rb:1220 approved by Sunny Bains
COMPRESSED PAGE SIZE
This was submitted as MySQL Bug 61456 and a patch provided by
Facebook. This patch follows the same idea, but instead of adding a
parameter to btr_cur_pessimistic_insert(), we simply remove the
btr_cur_optimistic_insert() call there and add it to the only caller
that needs it.
btr_cur_pessimistic_insert(): Do not try btr_cur_optimistic_insert().
btr_insert_on_non_leaf_level_func(): Invoke btr_cur_optimistic_insert()
before invoking btr_cur_pessimistic_insert().
btr_cur_pessimistic_update(): Clarify in a comment why it is not
necessary to invoke btr_cur_optimistic_insert().
btr_root_raise_and_insert(): Assert that the root page is not empty.
This could happen if a pessimistic insert (involving a split or merge)
is performed without first attempting an optimistic (intra-page) insert.
rb:1219 approved by Sunny Bains
btr_cur_optimistic_insert(): Remove a bogus assertion. The insert may
fail after reorganizing the page.
btr_cur_optimistic_update(): Do not attempt to reorganize compressed pages,
because compression may fail after reorganization.
page_copy_rec_list_start(): Use page_rec_get_nth() to restore to the
ret_pos, which may also be the page infimum.
rb:1221
The buffer for the current read row from each partition
(m_ordered_rec_buffer) used for sorted reads was
allocated on open and freed when the ha_partition handler
was closed or destroyed.
For tables with many partitions and big records this could
take up too much valuable memory.
Solution is to only allocate the memory when it is needed
and free it when nolonger needed. I.e. allocate it in
index_init and free it in index_end (and to handle failures
also free it on reset, close etc.)
Also only allocating needed memory, according to
partitioning pruning.
Manually tested that it does not use as much memory and
releases it after queries.
Problem description:
mysqlhotcopy fails if a view presents in the database.
Analysis:
Before 5.5 'FLUSH TABLES <tbl_name> ... WITH READ LOCK' will able
to get lock for all tables (i.e. base tables and view tables).
In 5.5 onwards 'FLUSH TABLES <tbl_name> ... WITH READ LOCK' for
'view tables' will not work, because taking flush locks on view
tables is not valid.
Fix:
Take flush lock for 'base tables' and read lock for 'view table'
separately.
Note: most of the patch has been backported from bug#13006947's patch
MASTER-MASTER AND USING SET USE
Problem:
=======
In a master-master set-up, a master can show a wrong
'SHOW SLAVE STATUS' output.
Requirements:
- master-master
- log_slave_updates
This is caused when using SET user-variables and then using
it to perform writes. From then on the master that performed
the insert will have a SHOW SLAVE STATUS that is wrong and
it will never get updated until a write happens on the other
master. On"Master A" the "exec_master_log_pos" is not
getting updated.
Analysis:
========
Slave receives a "User_var" event from the master and after
applying the event, when "log_slave_updates" option is
enabled the slave tries to write this applied event into
its own binary log. At the time of writing this event the
slave should use the "originating server-id". But in the
above case the sever always logs the "user var events"
by using its global server-id. Due to this in a
"master-master" replication when the event comes back to the
originating server the "User_var_event" doesn't get skipped.
"User_var_events" are context based events and they always
follow with a query event which marks their end of group.
Due to the above mentioned problem with "User_var_event"
logging the "User_var_event" never gets skipped where as
its corresponding "query_event" gets skipped. Hence the
"User_var" event always waits for the next "query event"
and the "Exec_master_log_position" does not get updated
properly.
Fix:
===
`MYSQL_BIN_LOG::write' function is used to write events
into binary log. Within this function a new object for
"User_var_log_event" is created and this new object is used
to write the "User_var" event in the binlog. "User var"
event is inherited from "Log_event". This "Log_event" has
different overloaded constructors. When a "THD" object
is present "Log_event(thd,...)" constructor should be used
to initialise the objects and in the absence of a valid
"THD" object "Log_event()" minimal constructor should be
used. In the above mentioned problem always default minimal
constructor was used which is incorrect. This minimal
constructor is replaced with "Log_event(thd,...)".
sql/log_event.h:
Replaced the default constructor with another constructor
which takes "THD" object as an argument.
CONNECTIONS IF SPE
Problem description: -ssl-key value is not validated, you can assign any bogus
text to --ssl-key and it is not verified that it exists, and more importantly,
it allows the client to connect to mysqld.
Fix: Added proper validations checks for --ssl-key.
Note:
1) Documentation changes require for 5.1, 5.5, 5.6 and trunk in the sections
listed below and the details are :
http://dev.mysql.com/doc/refman/5.6/en/ssl-options.html#option_general_ssl
and
REQUIRE SSL section of
http://dev.mysql.com/doc/refman/5.6/en/grant.html
2) Client having with option '--ssl', should able to get ssl connection. This
will be implemented as part of separate fix in 5.6 and trunk.
When resolving outer fields, Item_field::fix_outer_fields()
creates new Item_refs for each execution of a prepared statement, so
these must be allocated in the runtime memroot. The memroot switching
before resolving JOIN::having causes these to be allocated in the
statement root, leaking memory for each PS execution.
sql/item_subselect.cc:
addon, fix for 11829691, item could be created in
runtime memroot, so we need to use real_item instead.
ROWS THAT ARE EXPECTED
For non range/list partitioned tables (i.e. HASH/KEY):
When prune_partitions finds a multi-range list
(or in this test '<>') for a field of the partition index,
even if it cannot make any use of the multi-range,
it will continue with the next field of the partition index
and use that for pruning (even if it the previous
field could not be used). This results in partitions is
pruned away, leaving partitions that only matches
the last field in the partition index, and will exclude
partitions which might match any previous fields.
Fixed by skipping rest of partitioning key fields/parts
if current key field/part could not be used.
Also notice it is the order of the fields in the CREATE TABLE
statement that triggers this bug, not the order of fields in
primary/unique key or PARTITION BY KEY ().
It must not be the last field in the partitioning expression that
is not equal (or have a non single point range).
I.e. the partitioning index is created with the same field order
as in the CREATE TABLE. And for the bug to appear
the last field must be a single point and some previous field
must be a multi-point range.
