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The default CREATE TABLE options for Aria Engine in mariadb

The official document of mariadb does not mention the default CREATE TABLE options for tables using Aria Engine.  The default options are list as below:

  • TRANSACTIONAL,  the default value is TRANSACTIONAL=0, i.e., non-transactional.
  • ROW_FORMAT, the default value is ROW_FORMAT=PAGE, which may suits both transactional and non-transactional tables.
  • PAGE_CHECKSUM,  the default value will follow aria_page_checksum system variable, which has default value ON.

For the TRANSACTIONAL option, you may consider create a table as below(and ALTER the TRANSACTIONAL=1):

CREATE TABLE `test_table` (
`id` int(11) NOT NULL AUTO_INCREMENT,
PRIMARY KEY (`id`)
) ENGINE=Aria;

If you change the ROW_FORMAT to DYNAMIC or FIXED, everything just goes fine. But if you have ALTER the table with TRANSACTION=1 and change the ROW_FORMAT to DYNAMIC or FIXED, you may got a warning: 
SHOW WARNINGS;
+-------+------+----------------------------------------------------------+
| Level | Code | Message |
+-------+------+----------------------------------------------------------+
| Note  | 1478 | Row format set to PAGE because of TRANSACTIONAL=1 option |
+-------+------+----------------------------------------------------------+

And the ROW_FORMAT will not be altered(remains PAGE). So you could draw the conclusion that the default is TRANSACTION=0.

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