mark big_tables deprecated, the server can put temp tables on disk
as needed avoiding "table full" errors.
in case someone would really need to force a tmp table to be created
on disk from the start and for testing allow tmp_memory_table_size
to be set to 0.
fix tests to use that instead (and add a test that it actually
works).
make sure in-memory TREE size limit is never 0 (it's [ab]using
tmp_memory_table_size at the moment)
remove few sys_vars.*_basic tests
This allows one to run the test suite even if any of the following
options are changed:
- character-set-server
- collation-server
- join-cache-level
- log-basename
- max-allowed-packet
- optimizer-switch
- query-cache-size and query-cache-type
- skip-name-resolve
- table-definition-cache
- table-open-cache
- Some innodb options
etc
Changes:
- Don't print out the value of system variables as one can't depend on
them to being constants.
- Don't set global variables to 'default' as the default may not
be the same as the test was started with if there was an additional
option file. Instead save original value and reset it at end of test.
- Test that depends on the latin1 character set should include
default_charset.inc or set the character set to latin1
- Test that depends on the original optimizer switch, should include
default_optimizer_switch.inc
- Test that depends on the value of a specific system variable should
set it in the test (like optimizer_use_condition_selectivity)
- Split subselect3.test into subselect3.test and subselect3.inc to
make it easier to set and reset system variables.
- Added .opt files for test that required specfic options that could
be changed by external configuration files.
- Fixed result files in rockdsb & tokudb that had not been updated for
a while.
This patch introduces the optimization that allows range optimizer to
consider index range scans that are built employing NOT NULL predicates
inferred from WHERE conditions and ON expressions.
The patch adds a new optimizer switch not_null_range_scan.
Server and command line tools now support option --tls_version to specify the
TLS version between client and server. Valid values are TLSv1.0, TLSv1.1, TLSv1.2, TLSv1.3
or a combination of them. E.g.
--tls_version=TLSv1.3
--tls_version=TLSv1.2,TLSv1.3
In case there is a gap between versions, the lowest version will be used:
--tls_version=TLSv1.1,TLSv1.3 -> Only TLSv1.1 will be available.
If the used TLS library doesn't support the specified TLS version, it will use
the default configuration.
Limitations:
SSLv3 is not supported. The default configuration doesn't support TLSv1.0 anymore.
TLSv1.3 protocol currently is only supported by OpenSSL 1.1.0 (client and server) and
GnuTLS 3.6.5 (client only).
Overview of TLS implementations and protocols
Server:
+-----------+-----------------------------------------+
| Library | Supported TLS versions |
+-----------+-----------------------------------------+
| WolfSSL | TLSv1.1, TLSv1,2 |
+-----------+-----------------------------------------+
| OpenSSL | (TLSv1.0), TLSv1.1, TLSv1,2, TLSv1.3 |
+-----------+-----------------------------------------+
| LibreSSL | (TLSv1.0), TLSv1.1, TLSv1,2, TLSv1.3 |
+-----------+-----------------------------------------+
Client (MariaDB Connector/C)
+-----------+-----------------------------------------+
| Library | Supported TLS versions |
+-----------+-----------------------------------------+
| GnuTLS | (TLSv1.0), TLSv1.1, TLSv1.2, TLSv1.3 |
+-----------+-----------------------------------------+
| Schannel | (TLSv1.0), TLSv1.1, TLSv1.2 |
+-----------+-----------------------------------------+
| OpenSSL | (TLSv1.0), TLSv1.1, TLSv1,2, TLSv1.3 |
+-----------+-----------------------------------------+
| LibreSSL | (TLSv1.0), TLSv1.1, TLSv1,2, TLSv1.3 |
+-----------+-----------------------------------------+
post-merge changes:
* handle password expiration on old tables like everything else -
make changes in memory, even if they cannot be done on disk
* merge "debug" tests with non-debug tests, they don't use dbug anyway
* only run rpl password expiration in MIXED mode, it doesn't replicate
anything, so no need to repeat it thrice
* restore update_user_table_password() prototype, it should not change
ACL_USER, this is done in acl_user_update()
* don't parse json twice in get_password_lifetime and get_password_expired
* remove LEX_USER::is_changing_password, see if there was any auth instead
* avoid overflow in expiration calculations
* don't initialize Account_options in the constructor, it's bzero-ed later
* don't create ulong sysvars - they're not portable, prefer uint or ulonglong
* misc simplifications
This patch adds support for expiring user passwords.
The following statements are extended:
CREATE USER user@localhost PASSWORD EXPIRE [option]
ALTER USER user@localhost PASSWORD EXPIRE [option]
If no option is specified, the password is expired with immediate
effect. If option is DEFAULT, global policy applies according to
the default_password_lifetime system var (if 0, password never
expires, if N, password expires every N days). If option is NEVER,
the password never expires and if option is INTERVAL N DAY, the
password expires every N days.
The feature also supports the disconnect_on_expired_password system
var and the --connect-expired-password client option.
Closes#1166
The variable controls the amount of sampling analyze table performs.
If ANALYZE table with histogram collection is too slow, one can reduce the
time taken by setting analyze_sample_percentage to a lower value of the
total number of rows.
Setting it to 0 will use a formula to compute how many rows to sample:
The number of rows collected is capped to a minimum of 50000 and
increases logarithmically with a coffecient of 4096. The coffecient is
chosen so that we expect an error of less than 3% in our estimations
according to the paper:
"Random Sampling for Histogram Construction: How much is enough?”
– Surajit Chaudhuri, Rajeev Motwani, Vivek Narasayya, ACM SIGMOD, 1998.
The drawback of sampling is that avg_frequency number is computed
imprecisely and will yeild a smaller number than the real one.
Condition can be pushed from the HAVING clause into the WHERE clause
if it depends only on the fields that are used in the GROUP BY list
or depends on the fields that are equal to grouping fields.
Aggregate functions can't be pushed down.
How the pushdown is performed on the example:
SELECT t1.a,MAX(t1.b)
FROM t1
GROUP BY t1.a
HAVING (t1.a>2) AND (MAX(c)>12);
=>
SELECT t1.a,MAX(t1.b)
FROM t1
WHERE (t1.a>2)
GROUP BY t1.a
HAVING (MAX(c)>12);
The implementation scheme:
1. Extract the most restrictive condition cond from the HAVING clause of
the select that depends only on the fields that are used in the GROUP BY
list of the select (directly or indirectly through equalities)
2. Save cond as a condition that can be pushed into the WHERE clause
of the select
3. Remove cond from the HAVING clause if it is possible
The optimization is implemented in the function
st_select_lex::pushdown_from_having_into_where().
New test file having_cond_pushdown.test is created.
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
- Changed check of Global_only_lock to also include BACKUP lock.
- We store latest MDL_BACKUP_DDL lock in thd->mdl_backup_ticket to be able
to downgrade lock during copy_data_between_tables()
Added to new values to the server variable use_stat_tables.
The values are COMPLEMENTARY_FOR_QUERIES and PREFERABLY_FOR_QUERIES.
Both these values don't allow to collect EITS for queries like
analyze table t1;
To collect EITS we would need to use the syntax with persistent like
analyze table t1 persistent for columns (col1,col2...) index (idx1, idx2...) / ALL
Changing the default value from NEVER to PREFERABLY_FOR_QUERIES.
This patch introduces support for the system variable eq_range_index_dive_limit
that existed in MySQL starting from 5.6. The variable sets a limit for
index dives into equality ranges. Index dives are performed by optimizer
to estimate the number of rows in range scans. Index dives usually provide
good estimate but they are pretty expensive. To estimate the number of rows
in equality ranges statistical data on indexes can be employed. Its usage gives
not so good estimates but it's cheap. So if the number of equality dives
required by an index scan exceeds the set limit no dives for equality
ranges are performed by the optimizer for this index.
As the new system variable is introduced in a stable version the default
value for it is set to a special value meaning there is no limit for the number
of index dives performed by the optimizer.
The patch partially uses the MySQL code for WL 5957
'Statistics-based Range optimization for many ranges'.
