Lawrence, ----- Alkuperäinen viesti ----- Lähettäjä: "Lawrence Smith" <[EMAIL PROTECTED]> Vastaanottaja: "Heikki Tuuri" <[EMAIL PROTECTED]> Kopio: <[EMAIL PROTECTED]> Lähetetty: Sunday, February 01, 2004 1:03 PM Aihe: Re: Shrinking innodb datafiles?
> > --- Heikki Tuuri <[EMAIL PROTECTED]> wrote: > > > > > > > Just to confirm if I understand the situation > > > correctly: innodb datafiles cannot be reduced in > > size > > > to reclaim spaced freed by deleted data? > > > > you are right. > > Once again thanks. One absolutely last question (only > just occurred to me): will the space in the file used > by the deleted data be reused? yes, of course. Though, remember that if you randomly delete about 50 % of rows, it may happen that no 16 kB page or 1 MB extent becomes completely empty. Then the freed space can only be used by the same index tree from which the space was freed. The way to reorganize an InnoDB table is to run a 'null' ALTER TABLE: ALTER TABLE myinnodbtable TYPE = InnoDB; Be prepared for a very long run time, since the above command completely rebuilds the table. If you are using >= MySQL-4.1.1 and storing InnoDB tables to their own .ibd files, then the above command really frees the space to the OS. That is because the ALTER TABLE table is performed by creating a new .ibd file and deleting the old .ibd file. > Thx > > Lawrence Smith Best regards, Heikki Innobase Oy http://www.innodb.com InnoDB - transactions, row level locking, and foreign keys for MySQL InnoDB Hot Backup - a hot backup tool for InnoDB which also backs up MyISAM tables Order MySQL support from http://www.mysql.com/support/index.html -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
