PARTITION STATISTICS
Problem was the fix for bug#11756867; It always used the first
partitions, and stopped after it checked 10 [sub]partitions.
(or until it found a partition which would contain a match).
This results in bad statistics for tables where the first 10 partitions
don't represent the majority of the data (like when the first 10
partitions only contained a few rows in total).
The solution was to take statisics from the partitions containing
the most rows instead:
Added an array of partition ids which is sorted by number of records
in descending order.
this array is used in records_in_range to cover as many records as
possible in as few calls as possible.
Also changed the limit of how many partitions to use for the statistics
from a static max of 10 partitions, into a dynamic model:
Maximum number of partitions is now log2(total number of partitions)
taken from the ordered array.
It will continue calling partitions records_in_range until it has
checked:
(total rows in matching partitions) * (maximum number of partitions)
/ (number of used partitions)
Also reverted the changes for ha_partition::scan_time() and
ha_partition::estimate_rows_upper_bound() to before
the fix of bug#11756867. Since they are not as slow as
records_in_range.
leave the table unusable".
Failing ALTER statement on partitioned table could have left
this table in an unusable state. This has happened in cases
when ALTER was executed using "fast" algorithm, which doesn't
involve copying of data between old and new versions of table,
and the resulting new table was incompatible with partitioning
function in some way.
The problem stems from the fact that discrepancies between new
table definition and partitioning function are discovered only
when the table is opened. In case of "fast" algorithm this has
happened too late during ALTER's execution, at the moment when
all changes were already done and couldn't have been reverted.
In the cases when "slow" algorithm, which copies data, is used
such discrepancies are detected at the moment new table
definition is opened implicitly when new version of table is
created in storage engine. As result ALTER is aborted before
any changes to table were done.
This fix tries to address this issue by ensuring that "fast"
algorithm behaves similarly to "slow" algorithm and checks
compatibility between new definition and partitioning function
by trying to open new definition after .FRM file for it has
been created.
Long term we probably should implement some way to check
compatibility between partitioning function and new table
definition which won't involve opening it, as this should
allow much cleaner fix for this problem.
When having a sub query in partitioned innodb one could
make the partitioning engine to search for a 'index_next_same'
on a partition that had not been initialized.
Problem was that the subselect function looks at table->status
which was not set in the partitioning handler when it skipped
scanning due to no matching partitions found.
Fixed by setting table->status = STATUS_NOT_FOUND when
there was no partitions to scan. (If there are partitions to
scan, it will be set in the partitions handler.)
The ALTER PARTITION and SELECT seemed to be deadlocked
when having innodb_thread_concurrency = 1.
Problem was that there was unreleased latches
in the ALTER PARTITION thread which was needed
by the SELECT thread to be able to continue.
Solution was to release the latches by commit
before requesting upgrade to exclusive MDL lock.
Updated according to reviewers comments (3).
corruption on ADD PARTITION and LOCK TABLE
Bug#53770: Server crash at handler.cc:2076 on
LOAD DATA after timed out COALESCE PARTITION
5.5 fix for:
Bug#51042: REORGANIZE PARTITION can leave table in an
inconsistent state in case of crash
Needs to be back-ported to 5.1
5.5 fix for:
Bug#50418: DROP PARTITION does not interact with
transactions
Main problem was non-persistent operations done
before meta-data lock was taken (53770+53676).
And 53676 needed to keep the table/partitions opened and locked
while copying the data to the new partitions.
Also added thorough tests to spot some additional bugs
in the ddl_log code, which could result in bad state
between the .frm and partitions.
Collapsed patch, includes all fixes required from the reviewers.
As we check for the impossible partitions earlier, it's possible that we don't find any
suitable partitions at all. So this assertion just has to be corrected for this case.
per-file comments:
mysql-test/r/partition_innodb.result
Bug#55146 Assertion `m_part_spec.start_part == m_part_spec.end_part' in index_read_idx_map
test result updated.
mysql-test/t/partition_innodb.test
Bug#55146 Assertion `m_part_spec.start_part == m_part_spec.end_part' in index_read_idx_map
test case added.
sql/ha_partition.cc
Bug#55146 Assertion `m_part_spec.start_part == m_part_spec.end_part' in index_read_idx_map
Assertion changed to '>=' as the prune_partition_set() in the get_partition_set() can
do start_part= end_part+1 if no possible partitions were found.
value and NO_ZERO_DATE
The problem was that a older version of the error path for a
failed admin statement relied upon a few error conditions being
met in order to access a table handler, the first one being that
the table object pointer was not NULL. Probably due to chance,
in all cases a table object was closed but the reference wasn't
reset, the other conditions didn't evaluate to true. With the
addition of a new check on the error path, the handler started
being dereferenced whenever it was not reset to NULL, causing
problems for code paths which closed the table but didn't reset
the reference.
The solution is to reset the reference whenever a admin statement
fails and the tables are closed.
The default storage engine is changed from MyISAM to
InnoDB, in all builds except for the embedded server.
In addition, the following system variables are
changed:
* innodb_file_per_table is enabled
* innodb_strict_mode is enabled
* innodb_file_format_name_update is changed
to 'Barracuda'
The test suite is changed so that tests that do not
explicitly include the have_innodb.inc are run with
--default-storage-engine=MyISAM. This is to ease the
transition, so that most regression tests are run
with the same engine as before.
Some tests are disabled for the embedded server
regression test, as the output of certain statements
will be different that for the regular server
(i.e SELECT @@default_storage_engine). This is to
ease transition.
Conflicts:
Text conflict in client/mysqlbinlog.cc
Text conflict in mysql-test/Makefile.am
Text conflict in mysql-test/collections/default.daily
Text conflict in mysql-test/r/mysqlbinlog_row_innodb.result
Text conflict in mysql-test/suite/rpl/r/rpl_typeconv_innodb.result
Text conflict in mysql-test/suite/rpl/t/rpl_get_master_version_and_clock.test
Text conflict in mysql-test/suite/rpl/t/rpl_row_create_table.test
Text conflict in mysql-test/suite/rpl/t/rpl_slave_skip.test
Text conflict in mysql-test/suite/rpl/t/rpl_typeconv_innodb.test
Text conflict in mysys/charset.c
Text conflict in sql/field.cc
Text conflict in sql/field.h
Text conflict in sql/item.h
Text conflict in sql/item_func.cc
Text conflict in sql/log.cc
Text conflict in sql/log_event.cc
Text conflict in sql/log_event_old.cc
Text conflict in sql/mysqld.cc
Text conflict in sql/rpl_utility.cc
Text conflict in sql/rpl_utility.h
Text conflict in sql/set_var.cc
Text conflict in sql/share/Makefile.am
Text conflict in sql/sql_delete.cc
Text conflict in sql/sql_plugin.cc
Text conflict in sql/sql_select.cc
Text conflict in sql/sql_table.cc
Text conflict in storage/example/ha_example.h
Text conflict in storage/federated/ha_federated.cc
Text conflict in storage/myisammrg/ha_myisammrg.cc
Text conflict in storage/myisammrg/myrg_open.c
Conflicts:
Text conflict in mysql-test/r/partition_innodb.result
Text conflict in sql/field.h
Text conflict in sql/item.h
Text conflict in sql/item_cmpfunc.h
Text conflict in sql/item_sum.h
Text conflict in sql/log_event_old.cc
Text conflict in sql/protocol.cc
Text conflict in sql/sql_select.cc
Text conflict in sql/sql_yacc.yy
(regression)
Problem was that partition pruning did not exclude the
last partition if the range was beyond it
(i.e. not using MAXVALUE)
Fix was to not include the last partition if the
partitioning function value was not within the partition
range.
REORGANIZE PARTITION
There were several problems which lead to this this,
all related to bad error handling.
1) There was several bugs preventing the ddl-log to be used for
cleaning up created files on error.
2) The error handling after the copy partition rows did not close
and unlock the tables, resulting in deletion of partitions
which were in use, which lead InnoDB to put the partition to
drop in a background queue.
extraneous file
Online/fast ALTER TABLE of a partitioned table may leave
temporary file in database directory.
Fixed by removing unnecessary call to
handler::ha_create_handler_files(), which was creating
partitioning definition file.
on tables with partitions
Problem was that the handler function try_semi_consistent_read
was not propagated to the innodb handler.
Solution was to implement that function in the partitioning
handler.
index column
There was actually two problems
1) when clustered pk, order by non pk index should also
compare with pk as last resort to differ keys from each
other
2) bug in the index search handling in ha_partition (was
found when extending the test case
Solution to 1 was to include the pk in key compare if
clustered pk and search on other index.
Solution for 2 was to remove the optimization from
ordered scan to unordered scan if clustered pk.
Fixes:
Bug #18942: DROP DATABASE does not drop an orphan FOREIGN KEY constraint
Fix Bug#18942 by dropping all foreign key constraints at the end of
DROP DATABASE. Usually, by then, there are no foreign constraints
left because all of them are dropped when the relevant tables are
dropped. This code is to ensure that any orphaned FKs are wiped too.
Bug #29157: UPDATE, changed rows incorrect
Return HA_ERR_RECORD_IS_THE_SAME from ha_innobase::update_row() if no
columns were updated.
Bug #32440: InnoDB free space info does not appear in SHOW TABLE STATUS or I_S
Put information about the free space in a tablespace in
INFORMATION_SCHEMA.TABLES.DATA_FREE. This information was previously
available in INFORMATION_SCHEMA.TABLES.TABLE_COMMENT, but MySQL has
removed it from there recently.
The stored value is in kilobytes.
This can be considered as a permanent workaround to
http://bugs.mysql.com/32440. "Workaround" becasue that bug is about the
data missing from TABLE_COMMENT and this is actually not solved.
Problem was that the mix of handlers was not consistent between
CREATE and ALTER
changed so that it works like:
- All partitions must use the same engine
AND it must be the same as the table.
- if one does NOT specify an engine on the table level
then one must either NOT specify any engine on any
partition/subpartition OR for ALL partitions/subpartitions
Note: that after a table have been created, the storage engine
is specified for all parts of the table (table/partition/subpartition)
and so when using alter, one does not need to specify it (unless one
wants to change the storage engine, then one have to specify it on the
table level)
Problem: when alter to partitioned table,
it does not see it as change of engine.
Solution: If alter includes partitioning, check if it is possible
to change engines (eg. is the table referenced by a FK)
Before the fix:
ha_partition objects had ha_partition::m_part_info==NULL and that caused
crash
After:
- The new ha_partition::clone() function makes the clones use parent's
m_part_info value.
- The parent ha_partition object remains responsible for deallocation of
m_part_info.
