http://www.mysqldiary.com Exploring, Sharing and Discussing MySQL practice Mon, 18 Jul 2011 20:03:03 +0000 en hourly 1 http://wordpress.org/?v=3.3.1 http://www.mysqldiary.com/if-you-copy-a-myisam-table-with-primary-key-don%e2%80%99t-forget-to-order-the-rows-first/ http://www.mysqldiary.com/if-you-copy-a-myisam-table-with-primary-key-don%e2%80%99t-forget-to-order-the-rows-first/#comments Mon, 14 Mar 2011 19:02:23 +0000 Hazan Ilan http://www.mysqldiary.com/?p=189 In a case that you copy (INSERT INTO .. SELECT ..) a MyISAM table that have a PRIMARY key, it is much faster to insert the new rows in the primary key order: The insertion will be faster: because the primary key cannot disabled, every insertion will also updates the primary key. In a case [...]

]]> http://www.mysqldiary.com/if-you-copy-a-myisam-table-with-primary-key-don%e2%80%99t-forget-to-order-the-rows-first/feed/ 2 http://www.mysqldiary.com/the-battle-between-force-index-and-the-query-optimizer/ http://www.mysqldiary.com/the-battle-between-force-index-and-the-query-optimizer/#comments Mon, 25 Oct 2010 21:15:41 +0000 Hazan Ilan http://www.mysqldiary.com/?p=146 Query Optimizer is a part of the server that takes a parsed SQL query and produces a query execution plan. MySQL Query Optimizer uses (as one of its parameters) the stored key distribution (Cardinality) mechanism to determine the order in which tables should be joined, when you perform a join on something other than a [...]

]]> http://www.mysqldiary.com/the-battle-between-force-index-and-the-query-optimizer/feed/ 2 http://www.mysqldiary.com/user-defined-variables/ http://www.mysqldiary.com/user-defined-variables/#comments Wed, 02 Jun 2010 21:04:19 +0000 Hazan Ilan http://www.mysqldiary.com/?p=7 When I have discovered MySQL User-defined variables at the first time, I didn’t pay much attention to them and didn’t realize their strength. At first, one can think that they are just one of the many unnoticed MySQL features. Well, I was wrong. Here, I will try to summarize their strength, though I think there is [...]

]]> http://www.mysqldiary.com/user-defined-variables/feed/ 23 http://www.mysqldiary.com/the-fading-of-query-cache-limitation/ http://www.mysqldiary.com/the-fading-of-query-cache-limitation/#comments Tue, 15 Dec 2009 19:31:42 +0000 Hazan Ilan http://www.mysqldiary.com/?p=50 There is no question about the MySQL Query Cache greatness.  The MySQL Query Cache feature started his way with some limitations.  However, in time, there were a lot of improvements (fixing) for those limitations. One should test his MySQL version with the Query Cache limitations before using it. Here are some improved limitations I found [...]

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