… compressed. Unfortunately MySQL does not provide compressed BLOB/TEXT columns (I would really love to have COMPRESSED attribute for the BLOB/TEXT columns… with with console MySQL tools. Some people get best of both worlds by taking COMPRESS/UNCOMPRESS functions from the MySQL code and having…
Post: Bug#12704861
November 20, 2011 By 1 Comment
… in MySQL 5.1.60. I’ll repeat here the full documentation from the release notes: “InnoDB Storage Engine: Data from BLOB…. The problem that this function was trying to address was that when we did mtr_commit() the BLOB writes before the mtr… make the freed clustered index pages unavailable to the BLOB allocation. This function is also a likely culprit of InnoDB hangs that…
Post: Recover BLOB fields
July 1, 2010 By 4 Comments
…=latin1 Here COMPACT format is used, which is default in MySQL >= 5.1. The record consists of four parts: Offsets. Effectively… brings prerequisites to successfully recover a record with BLOB : all pieces of the BLOB field must be reachable by pointers. That means… values format. BLOBs are printed in a hex form – 0ACD86… To upload the table back you should utilize UNHEX function: mysql> LOAD DATA…
Post: Adventures in archiving
February 11, 2013 By 16 Comments
…. InnoDB’s inbuilt row compression MySQL‘s inbuilt compress() function leveraging zlib to provide compression of data. MySQL‘s Archive storage engine. Tooling… `compressed_data` ( `id` int(11) NOT NULL AUTO_INCREMENT, `dat` blob, PRIMARY KEY (`id`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1; CREATE TABLE…
Post: MySQL EXPLAIN limits and errors.
July 24, 2006 By 6 Comments
… known – for example BLOB fields can’t work with in memory temporary table. The other thing – since MySQL 4.1 sorting can… 100 rows/sec. No info about functions cost Since MySQL 5.0 you may use user functions in your query which may also…. The cost of functions is also not used in optimization which may produce suboptimal plans if stored functions are used in queries…
Post: 10+ Ways to Crash or Overload MySQL
November 13, 2007 By 20 Comments
… keep max_prepared_stmt_count very low. Prepared Statements and Blob Data If you’re want to get memory consumed by… being functional. General Overload As MySQL does not have much of resource utilization control you can simply run heavy queries to get MySQL Server barely functional. The…
Post: Innodb row size limitation
April 7, 2011 By 12 Comments
… version specific, see http://www.mysqlperformanceblog.com/2010/02/09/blob-storage-in-innodb/ for further reference). It’s worth mentioning… the result of the COMPRESS function is always binary, so for example, you should use a BLOB instead of a TEXT column… if you choose XML as format and you use MySQL‘s built in functions for handling this data. This approach, however, does…
Post: When should you store serialized objects in the database?
January 21, 2010 By 47 Comments
… changed from storing data in MySQL columns to serializing data and just storing it inside TEXT/BLOB columns. It seems that since… to one piece of data in a very large blob, the effort MySQL has to go to is greatly increased. The second… that there is a clear loss in functionality. You can no longer easily perform aggregation functions on the data (MIN, MAX, AVG…
Post: Falcon Storage Engine Design Review
January 12, 2007 By 19 Comments
…been implemented outside of MySQL Storage Engine level for MySQL – reading rows in their… internal hidden primary key) but this functionality is not exported well as it…Blob handling optimizations Jim loves BLOBs as his own child, so Falcon is optimized in Blob handling for example having direct blob…
Post: Percona Server 5.1.50-rel12.1
October 14, 2010 By 2 Comments
… available for download. Functionality Added or Changed Percona Server 5.1.50-rel12.1 is now based on MySQL 5.1.50… Kinoshita) remove_eol_carret – Implemented a MySQL client option to handle end-of-line in BLOB fields differently. This change also fixed… #625066 – Fixed a problem handling end-of-line in BLOB fields in the MySQL client. (Sasha Pachev) Bug #640924 – Fixed a crash…
