Some tests drop the default mtr database "test". This may fail due
to the directory not being empty. InnoDB may not delete all tables
immediately, due to the "background drop table queue" or its
replacement in commit 1bd681c8b3
(the purge of history would clean up after a DDL operation during
which the server was killed).
Let us try to avoid "drop database test" whenever it is easily possible.
Where it is not, SET GLOBAL innodb_max_purge_lag_wait=0 will ensure
that the replacement of the "background drop table queue" will have
completed its job.
Removing DEFAULT from INFORMATION_SCHEMA columns.
DEFAULT in read-only tables is rather meaningless.
Upgrade should go smoothly.
Also fixes:
MDEV-20254 Problems with EMPTY_STRING_IS_NULL and I_S tables
optimize_schema_tables_memory_usage() crashed when its argument included
TABLE struct that was not fully initialized.
To prevent such a crash, we check if a table is an information schema table at
the beginning of each iteration.
Closes#1768
The mysql.user view password_expired column should display the right
result, in sync with whether an account has its password expired or not
For mariadb 10.4+ upgrades before this commit, the mysql.user view needs
to be dropped and recreated to actually make the view display the
correct value for the password_expired column.
This was caused by two different bugs:
1) Information_schema tables where not locked by lock_tables, but
get_lock_data() was not filtering these out. This caused a crash when
mysql_unlock_some_tables() tried to unlock tables early, including
not locked information schema tables.
Fixed by not locking SYSTEM_TMP_TABLES
2) In some cases the optimizer will notice that we do not need to read
the information_schema tables at all. In this case
join_tab->read_record is not set, which caused a crash in
get_schema_tables_result()
Fixed by ignoring const tables in get_schema_tables_result()
I_S tables were materialized too late, an attempt to use table
statistics before the table was created caused a crash.
Let's move table creation up. it only needs read_set to
be calculated properly, this happens in JOIN::optimize_inner(),
after semijoin transformation.
Note that tables are not populated at that point, so most of the
statistics would make no sense anyway. But at least field sizes
will be correct. And it won't crash.
disable thd->count_cuted_fields when populating internal temporary
tables for I_S, because this is how SELECT works standalone.
And if the SELECT is a part of INSERT or UPDATE or RETURN or SET or
anything else that enables thd->count_cuted_fields, this counting should
only apply when storing the result of the SELECT in a field or a
variable, not when populating internal temporary tables for I_S.
In case of NATURAL JOIN / USING mark all field (one table can not be opened
in any case so optimisation does not worth it).
IMHO table should be checked for used fields and filled after prepare,
when we will fave whole info about used fields but it is too big change
for a bugfix. Which will be made later by Serg patch
Also fixes:
MDEV-21487: Implement option for mysql_upgrade that allows root@localhost to be replaced
MDEV-21486: Implement option for mysql_install_db that allows root@localhost to be replaced
Add user mariadb.sys to be definer of user view
(and has right on underlying table global_priv for
required operation over global_priv
(SELECT,UPDATE,DELETE))
Also changed definer of gis functions in case of creation,
but they work with any definer so upgrade script do not try
to push this change.
This task involves the implementation for the optimizer trace.
This feature produces a trace for any SELECT/UPDATE/DELETE/,
which contains information about decisions taken by the optimizer during
the optimization phase (choice of table access method, various costs,
transformations, etc). This feature would help to tell why some decisions were
taken by the optimizer and why some were rejected.
Trace is session-local, controlled by the @@optimizer_trace variable.
To enable optimizer trace we need to write:
set @@optimizer_trace variable= 'enabled=on';
To display the trace one can run:
SELECT trace FROM INFORMATION_SCHEMA.OPTIMIZER_TRACE;
This task also involves:
MDEV-18489: Limit the memory used by the optimizer trace
introduces a switch optimizer_trace_max_mem_size which limits
the memory used by the optimizer trace. This was implemented by
Sergei Petrunia.
Part of MDEV-5336 Implement LOCK FOR BACKUP
Originally both table metadata lock and global read lock protection
were acquired before getting TABLE from table cache. This will be
reordered in a future commit with MDL_BACKUP_XXX locks so that we
first take table metadata lock, then get TABLE from table cache, then
acquire analogue of global read lock.
This patch both simplifies FLUSH TABLES code, makes FLUSH TABLES to
lock less and also enables FLUSH TABLES code to be used with backup
locks.
The usage of FLUSH TABLES changes slightly:
- FLUSH TABLES without any arguments will now only close not used tables
and tables locked by the FLUSH TABLES connection. All not used table
shares will be closed.
Tables locked by the FLUSH TABLES connection will be reopened and
re-locked after all others has stoped using the table (as before).
If there was no locked tables, then FLUSH TABLES is instant and will
not cause any waits.
FLUSH TABLES will not wait for any in use table.
- FLUSH TABLES with a table list, will ensure that the tables are closed
before statement returns. The code is now only using MDL locks and not
table share versions, which simplices the code greatly. One visible
change is that the server will wait for the end of the transaction that
are using the tables. Before FLUSH TABLES only waited for the statements
to end.
Signed-off-by: Monty <monty@mariadb.org>
Implement according to standard SQL specification 2008.
The check_constraints table is used for fetching metadata about
the constraints defined for tables in all databases.
