I upgraded my Mac OS X Leopard to Snow Leopard a couple days ago. Everything seems to be fine, system runs faster than before in general. But a couple of softwares doesnt work compatible with SL.

The 1st one is mysql, after upgrading, it's completely gone, I just cannt find it. Then I try to reinstall it with macport, but zlib doesnt work with SL too! So, install mysql manually may be the best way.

Solution: Compiling MySQL on Snow Leopard

The 2nd one is mysql-gem. When I wanna reload db, it shows "uninitialized constant MysqlCompat::MysqlRes" error. To fix this, specify ARCHFLAGS when you install the 'mysql' gem:

sudo env ARCHFLAGS="-arch x86_64" gem install mysql -- --with-mysql-config=/usr/local/mysql/bin/mysql_config

refer to: Error: uninitialized constant MysqlCompat::MysqlRes

The 3rd one is thin-gem. Well, easy to fix:

sudo gem update thin