Multiple db's or just one?

[acctman]

would i gain any noticable performance by using multiple databases? example would be a database that holds country, city, and zip code info. then the main user database.

[dreamwest]

If your after speed - Whatever you gain would be lost connecting to multiple databases

 

Unless you have millions of queries an hour i wouldnt worry about it. Your better of caching content and compressing data to reduce server load:

 

#increase speed and preserve bandwidth
<ifmodule mod_php4.c>
php_value zlib.output_compression 16386
</ifmodule>

# 1 WEEK
<FilesMatch "\.(jpg|jpeg|gif|ico|png)$">
Header set Cache-Control "max-age=604800, public"
</FilesMatch>

# 5 MIN
<FilesMatch "\.(css|js|swf|flv)$">
Header set Cache-Control "max-age=172800, private, proxy-revalidate"
</FilesMatch>

[Mchl]

If these databases resided on single database server you would gain nothing.