-----------------------------+--------------------------------+
| SYSTEM_TIME                                | <= MariaDB 10.3.6 only         |
+--------------------------------------------+--------------------------------+
| VERSIONING                                 | <= MariaDB 10.3.6 only         |
+--------------------------------------------+--------------------------------+
| WITHOUT                                    | <= MariaDB 10.3.6 only         |
+--------------------------------------------+--------------------------------+

Function Names
--------------

If the IGNORE_SPACE SQL_MODE flag is set, function names become reserved words.

URL: https://mariadb.com/kb/en/reserved-words/https://mariadb.com/kb/en/from_unixtime/               |
+---------------------------------------------------------+

SELECT STR_TO_DATE('Wednesday23423, June 2, 2014', '%W, %M %e, %Y');
+--------------------------------------------------------------+
| STR_TO_DATE('Wednesday23423, June 2, 2014', '%W, %M %e, %Y') |
+--------------------------------------------------------------+
| NULL                                                         |
+--------------------------------------------------------------+
1 row in set, 1 warning (0.00 sec)

SHOW WARNINGS;
+---------+------+-------------------------------------------------------------
---------------------+
| Level   | Code | Message                                                    
           |
+---------+------+-------------------------------------------------------------
---------------------+
| Warning | 1411 | Incorrect datetime value: 'Wednesday23423, June 2, 2014'
for function str_to_date |
+---------+------+-------------------------------------------------------------
---------------------+

SELECT STR_TO_DATE('Wednesday23423, June 2, 2014', '%W%#, %M %e, %Y');
+----------------------------------------------------------------+
| STR_TO_DATE('Wednesday23423, June 2, 2014', '%W%#, %M %e, %Y') |
+----------------------------------------------------------------+
| 2014-06-02                                                     |
+----------------------------------------------------------------+

URL: https://mariadb.com/kb/en/str_to_date/dding a comment:

ALTER TABLE t1 
 ENGINE = InnoDB
 COMMENT = 'First of three tables containing usage info';

Rebuilding the table (the previous example will also rebuild the table if it
was already InnoDB):

ALTER TABLE t1 FORCE;

Dropping an index:

ALTER TABLE rooms DROP INDEX u;

Adding a unique index:

ALTER TABLE rooms ADD UNIQUE INDEX u(room_number);

From MariaDB 10.5.3, adding a primary key for an application-time period table
with a WITHOUT OVERLAPS constraint:

ALTER TABLE rooms ADD PRIMARY KEY(room_number, p WITHOUT OVERLAPS);

From MariaDB 10.8.1, ALTER query can be replicated faster with the setting of

SET @@SESSION.binlog_alter_two_phase = true;

prior the ALTER query. Binlog would contain two event groups

| master-bin.000001 | 495 | Gtid              |         1 |         537 | GTID
0-1-2 START ALTER                                        |
| master-bin.000001 | 537 | Query             |         1 |         655 | use
`test`; alter table t add column b int, algorithm=inplace |
| master-bin.000001 | 655 | Gtid              |         1 |         700 | GTID
0-1-3 COMMIT ALTER id=2                                  |
| master-bin.000001 | 700 | Query             |         1 |         835 | use
`test`; alter table t add column b int, algorithm=inplace |

of which the first one gets delivered to replicas before ALTER is taken to
actual execution on the primary.

URL: https://mariadb.com/kb/en/alter-table/