Software Update: MySQL 3.23.41

Xoror reported that the MySQL dev team has released a new version of their well-known open source database. Version .41 contains a number of bug fixes and furthermore, support for <4GB InnoDB row added. You can take down the source and binaries via this link†

• Added option –sql-mode=option[,option[,option]† See section 4.1.1 mysqld Command-line Options.
• Fixed possible problem with shutdown on Solaris where the .pid file wasn’t deleted.
• InnoDB now supports < 4 GB rows. The former limit was 8000 bytes.
• The doublewrite file flush method is used in InnoDB. It reduces the need for Unix fsync calls to a fraction and improves performance on most Unix flavors.
• You can now use the InnoDB Monitor to print a lot of InnoDB state information, including locks, to the standard output; useful in performance tuning.
• Several bugs which could cause hangs in InnoDB have been fixed.
• Split record_buffer to record_buffer and record_rnd_buffer. To make things compatible to previous MySQL versions, if record_rnd_buffer is not set, then it takes the value of record_buffer.
• Fixed optimizing bug in ORDER BY where some ORDER BY parts where wrongly removed.
• Fixed overflow bug with ALTER TABLE and MERGE tables.
• Added prototypes for my_thread_init() and my_thread_end() to `mysql_com.h’
• Added option –safe-user-create to mysqld.
• Added options to the –ansi startup options to let the user decide which ansi options one to enable.
• Fixed bug in SELECT DISTINCT … HAVING that casued error message Can’t find record in ‘#…

MySQL 3.23.41 is especially interesting for InnoDB users or people who are considering using InnoDB tables. InnoDB has support for row-level locking and transactions. Both features are missing from the standard MyISAM table format of MySQL. Below is the information from the InnoDB site†

Binary release of MySQL/InnoDB-3.23.41 for Unix now available at the MySQL website. Also the source available. Windows version of .41 is expected within a week. Version 3.23.41 is an important release of InnoDB: support for big BLOB and TEXT columns is now included in the binary release, and the doublewrite flush method removes a performance problem experienced on some Unix flavors. Main changes in InnoDB:

• Maximum row size is now 4 GB, while the previous limit was 8000 bytes.

• You can use raw disk partitions as data files.
• The ‘doublewrite’ file flush method is used: it improves safety of crash recovery and reduces the need for Unix fsync calls to a fraction, improving performance on most Unix flavors.
• You can start the InnoDB Monitor through the following SQL statement:

  CREATE TABLE innodb_monitor(a int) type = innodb;

  To stop the monitor call DROP TABLE innodb_monitor. InnoDB Monitor prints a lot of InnoDB state information, including locks, to the standard output, which is useful in performance tuning.

• Several bugs which could cause hangs have been fixed.