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  1. MariaDB Server
  2. MDEV-9200

Better BLOB handling support im Aria Storage Engine

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      I have got following Table

      create Table:

      CREATE TABLE `mytable` (
        `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
        `title` varchar(255) NOT NULL DEFAULT '',
        `icon` blob,
        PRIMARY KEY (`id`)
      ) ENGINE=aria DEFAULT CHARSET=latin1
      

      If i do requests on this table the blob field named icon is always read even so i don't request its contents which makes the querys really slow.

      i just do a

      SELECT id,title FROM mytable 
      

      all the blob fields are read from disk.
      If i do it like

      SELECT id,title FROM mytable where id in (....) 
      

      all blob fields of all specified rows are read.

      I looked at the internet before and found the following claim that blob support in Aria ist better than in MyISAM.

      https://mariadb.com/kb/en/mariadb/aria-faq/
      -What are the 'design goals' in Aria?

      -Better blob handling (than is currently offered in MyISAM, at a minimum).
      -No memory copying or extra memory used for blobs on insert/update.
      -Blobs allocated in big sequential blocks - Less fragmentation over time.
      -Blobs are stored so that Aria can easily be extended to have access to any part of a blob with a single fetch in the future.

      Has nothing of the above done yet?

      I tried InnoDB but that ended in a total database server crash with a lot of data corruption in the database itself, i was not able to recover my test data. I could crash the server with just two simple SQL statements (tested on mysql).

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            Unassigned Unassigned
            MichaelSchwab Michael Schwab
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