Hi Jamie, Yes, when tables are made "smaller" in MySQL, the file size isn't actually reduced. I guess it shouldn't usually make a speed difference unless your SELECTs are doing a table scan. Reads that use an index shouldn't really be affected, I don't think.
If you want to reclaim the deleted space, you can do so by running OPTIMIZE TABLE. Be aware that it may take awhile to run on a large table! Hope that helps. Matt ----- Original Message ----- From: "jamie murray" Sent: Wednesday, December 17, 2003 2:42 PM Subject: high water mark Guys, Does mysql record the high water mark in it's tables. If so can it be shrunken after a mass delete. I am new to mysql and haven't seen any info on this so I'm not sure if it exists in this database. I am asking this because after I deleted a lot of data from one table a simple select is now very slow, this would make me think that like in oracle the query is reading all blocks up to the high water mark even thought there is no data there. I am familiar with oracle but not MySql so excuse my ignorance if it is showing with this particular topic. Cheers -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]