Re: A couple of questions...

Addressed to: =?iso-8859-1?Q?Daniel_Als=E9n?= <daniel@innehallsbolaget.com> php-general@lists.php.net ** Reply to note from =?iso-8859-1?Q?Daniel_Als=E9n?= <daniel@innehallsbolaget.com> Fri, 24 Nov 2000 10:20:47 +0100 > > Hi guys - a couple of questions: > > - When working with MySQL. Should i close the connection at the end of > the code of every question to the database (mysql_close)? Is there an > uneccessary load on the server if i don t? > NO! Opening the connection is often the biggest delay in using a database. If you do only one query per page, there is no reason to close anything at all. PHP will do it for you when the script ends. PHP is very good at garbage collection. If you do many queries in one script, it is wise to use mysql_free_result( $Result ) when you are done with each result set to save memory. (Except the last, which will be closed by PHP as soon as the script ends.) If you don't open too many different databases from your web server you might want to use persistant connections to reduce the number of connects even more. mysql_pconnect() (I think.) I do run a large number virtual domains on a single server, so I don't use it. Eventually you end up trying to open Num_virtual_hosts * Num_Apache_Threads connections. Usually the database server runs out of connections and things fail. > - What methods should i use to speed up database searches? Is there > anything more i can do excepts from indexing the fields im using for the > search? Try your queries from the command line interpreter, and use EXPLAIN. http://www.mysql.com/documentation/mysql/commented/manual.php?section=EXPLAIN > - How do i easily decide in what order listing of a table is returned? ORDER BY in the query. If you haven't yet, you should look over the MySQL manual. Section 7, the command reference, is very important to know your way around. MySQL can do quite a bit for you before the data is passed to PHP. Rick Widmer Internet Marketing Specialists www.developersdesk.com When all you have is a hammer, everything looks like a nail.