David Wheeler wrote:
On Sunday, November 24, 2002, at 01:08 PM, Bas A.Schulte wrote:
I'm wondering if I would gain (some) performance by preparing my sql
statements once during ChildInit when using MySQL? Does it cache
execution plans for sql statements? I know it makes a big difference
on Oracle but I'm not sure what MySQL is like in this respect.
MySQL doesn't have a prepared statement feature, so you wouldn't get the
same kind of performance gain that you would with Oracle. That said,
DBD::mysql does a bit of munging with your statements, and if you use
prepare(), it does that munging only once per statement.
The upshot: Use prepare() whenever possible to maximize performance.
Even better, used prepare_cached() for statements you'll be using a lot,
and then they'll be prepared only the first time prepare() is called
(per Apache child). Doing so will also make it easier to gain the
performance benefit if you later decide to switch to a database such as
Oracle that supports prepared statements in the database.
What David said, plus your friendly docs:
http://perl.apache.org/search/swish.cgi?query=prepare_cached&sbm=SecE&submit=search
__________________________________________________________________
Stas Bekman JAm_pH ------> Just Another mod_perl Hacker
http://stason.org/ mod_perl Guide ---> http://perl.apache.org
mailto:[EMAIL PROTECTED] http://use.perl.org http://apacheweek.com
http://modperlbook.org http://apache.org http://ticketmaster.com
