Problem:
========
Server fails to notify the engine by not setting the ADD_PK_INDEX and
DROP_PK_INDEX When there is a
i) Change in candidate for primary key.
ii) New candidate for primary key.
Fix:
====
Server sets the ADD_PK_INDEX and DROP_PK_INDEX while doing alter for the
above problematic case.
The error message modified.
Then the TABLE_SHARE::error_table_name() implementation taken from 10.3,
to be used as a name of the table in this message.
Locked_tables_list::unlock_locked_tables
Similarly to regular DROP TABLE, don't leave locked tables mode if CREATE OR
REPLACE dropped temporary table but failed to cerate new one.
The problem is that there's no track of which temporary table was "locked" by
LOCK TABLES.
ALTER TABLE locks the table with TL_READ_NO_INSERT, to prevent the
source table modifications while it's being copied. But there's an
indirect way of modifying a table, via cascade FK actions.
After previous commits, an attempt to modify an FK parent table
will cause FK children to be prelocked, so the table-being-altered
cannot be modified by a cascade FK action, because ALTER holds a
lock and prelocking will wait.
But if a new FK is being added by this very ALTER, then the target
table is not locked yet (it's a temporary table). So, we have to
lock FK parents explicitly.
Problem was that the number of NULL bit's was record wrong in the
.frm file because there could be more fields marked NOT_NULL after the
number of not_null fields where recorded.
Fixed by copying test for virtual fields from prepare_create_field()
The code change, only the test, doesn't have to be merged to 10.3
as this is fixed there.
MEMORY table could be renamed into a non-extistent database.
rename() is documented to return ENOENT when the source file does not
exist OR when the target directory not exist. Nonexistent source .frm
file is ok (table can still exist in the engine), nonexistent target
directory is not.
Make my_rename to use ENOTDIR for the latter case. Make RENAME TABLE
issue an appropriate error ("unknown database" instead of "unknown table")
Crash happened because in discover, table->work_part_info was not properly
reset before execution.
Fixed by resetting before calling execute alter table, create table or
mysql_create_frm_image.
Crash happened when deleting all columns that was part of a check constraint
The bug was that read map for from table was used when
checking CHECK constraint and was not properly reset
in copy_data_between_tables()
Problem was that if copy_data_between_tables() didn't do proper
clean up in case of failures:
- copy object was not properly freed
- end_bulk_insert() was not called
- mysql_trans_prepare_alter_copy_data() set THD->transaction.on to
false which was not properly restored
The last part caused a crash in Aria as Aria depends on that THD
is correct.
Other things:
- Reset info->switched_transactional after usage (safety)
- Reset bulk_insert_single_undo (safety)
Part one, non-temporary tables.
Rrenaming a column can make destructive changes
to the TABLE. This TABLE cannot be used anymore
and needs to be reopened even if ALTER TABLE
was aborted with an error.
don't try to convert a default value string from a user character set
into a column character set, if this particular default value string did
not came from the user at all (that is, if it's an ALTER TABLE and the
default value string is the *old* default value of the unaltered
column).
This used to crash, because old defaults are allocated on the old
table's memroot, which is freed mid-ALTER when the old table is closed.
So thd->rollback_item_tree_changes() at the end of the ALTER was writing
into the freed memory.
ALTER TABLE ... ADD PARTITION modifies the open TABLE structure,
and sets table->need_reopen=1 to reset these modifications
in case of an error.
But under LOCK TABLES the table isn't get reopened, despite need_reopen.
Fixed by reopening need_reopen tables under LOCK TABLE.
PREBUILT->TABLE->N_MYSQL_HANDLES_OPENED == 1
ANALYSIS:
=========
Adding unique index to a InnoDB table which is locked as
mutliple instances may trigger an InnoDB assert.
When we add a primary key or an unique index, we need to
drop the original table and rebuild all indexes. InnoDB
expects that only the instance of the table that is being
rebuilt, is open during the process. In the current
scenario we have opened multiple instances of the table.
This triggers an assert during table rebuild.
'Locked_tables_list' encapsulates a list of all
instances of tables locked by LOCK TABLES statement.
FIX:
===
We are now temporarily closing all the instances of the
table except the one which is being altered and later
reopen them via Locked_tables_list::reopen_tables().
If a crash occurs during ALTER TABLE…ALGORITHM=COPY, InnoDB would spend
a lot of time rolling back writes to the intermediate copy of the table.
To reduce the amount of busy work done, a work-around was introduced in
commit fd069e2bb3 in MySQL 4.1.8 and 5.0.2,
to commit the transaction after every 10,000 inserted rows.
A proper fix would have been to disable the undo logging altogether and
to simply drop the intermediate copy of the table on subsequent server
startup. This is what happens in MariaDB 10.3 with MDEV-14717,MDEV-14585.
In MariaDB 10.2, the intermediate copy of the table would be left behind
with a name starting with the string #sql.
This is a backport of a bug fix from MySQL 8.0.0 to MariaDB,
contributed by jixianliang <271365745@qq.com>.
Unlike recent MySQL, MariaDB supports ALTER IGNORE. For that operation
InnoDB must for now keep the undo logging enabled, so that the latest
row can be rolled back in case of an error.
In Galera cluster, the LOAD DATA statement will retain the existing
behaviour and commit the transaction after every 10,000 rows if
the parameter wsrep_load_data_splitting=ON is set. The logic to do
so (the wsrep_load_data_split() function and the call
handler::extra(HA_EXTRA_FAKE_START_STMT)) are joint work
by Ji Xianliang and Marko Mäkelä.
The original fix:
Author: Thirunarayanan Balathandayuthapani <thirunarayanan.balathandayuth@oracle.com>
Date: Wed Dec 2 16:09:15 2015 +0530
Bug#17479594 AVOID INTERMEDIATE COMMIT WHILE DOING ALTER TABLE ALGORITHM=COPY
Problem:
During ALTER TABLE, we commit and restart the transaction for every
10,000 rows, so that the rollback after recovery would not take so long.
Fix:
Suppress the undo logging during copy alter operation. If fts_index is
present then insert directly into fts auxiliary table rather
than doing at commit time.
ha_innobase::num_write_row: Remove the variable.
ha_innobase::write_row(): Remove the hack for committing every 10000 rows.
row_lock_table_for_mysql(): Remove the extra 2 parameters.
lock_get_src_table(), lock_is_table_exclusive(): Remove.
Reviewed-by: Marko Mäkelä <marko.makela@oracle.com>
Reviewed-by: Shaohua Wang <shaohua.wang@oracle.com>
Reviewed-by: Jon Olav Hauglid <jon.hauglid@oracle.com>
