note 79178 added to function.PDO-prepare

Using prepared SELECT statements on a MySQL database prior to MySQL 5.1.17 can lead to SERIOUS performance degradation. Quote from http://dev.mysql.com/doc/refman/5.1/en/query-cache.html : >> The query cache is not used for server-side prepared statements before MySQL 5.1.17 >> << The MySQL query cache buffers complete query results and is used to satisfy repeated identical queries if the underlying tables do not change in the meantime - just what happens all the time in a typical web application. It speeds up queries by a several hundred to a several thousand percent. Obviously, it doesn't make much sense to give up query caching for the relatively small performance benefit of prepared statements (i.e. the DBMS not having to parse and optimize the same query multiple times) - so using PDO->query() for SELECT statements is probably the better choice i you're connecting to MySQL < 5.1.17. ---- Server IP: 217.13.201.10 Probable Submitter: 217.184.142.46 ---- Manual Page -- http://www.php.net/manual/en/function.PDO-prepare.php Edit -- https://master.php.net/note/edit/79178 Del: integrated -- https://master.php.net/note/delete/79178/integrated Del: useless -- https://master.php.net/note/delete/79178/useless Del: bad code -- https://master.php.net/note/delete/79178/bad+code Del: spam -- https://master.php.net/note/delete/79178/spam Del: non-english -- https://master.php.net/note/delete/79178/non-english Del: in docs -- https://master.php.net/note/delete/79178/in+docs Del: other reasons-- https://master.php.net/note/delete/79178 Reject -- https://master.php.net/note/reject/79178 Search -- https://master.php.net/manage/user-notes.php