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Status: 500 Internal Server Error   uninitialized constant MysqlCompat::MysqlRes

Posted on 2009-12-16
Medium Priority
Last Modified: 2013-11-13
I have this error:
Status: 500 Internal Server Error
  uninitialized constant MysqlCompat::MysqlRes

Already followed this tutorial: http://boonedocks.net/mike/archives/175-MAMP-and-the-Ruby-MySQL-Gem.html

But still the same problem.
At the RoR server localhost:3000 page i get the RoR-message "we're sorry..."
Question by:ads711
  • 4
LVL 14

Expert Comment

ID: 26068898
Are you on a mac?  I presume so since you're talking about MAMP.

Did you happen to restart your application after you recompiled the gem?

sudo gem update mysql

Maybe that'll reinstall what you need?

Author Comment

ID: 26069251
yes, i'm on mac.
I've restarted the compiled gem.

With "sudo gem update mysql" i get:
"Updating installed gems
Nothing to update"
LVL 14

Expert Comment

ID: 26072871
What version of rails are you using?
You should see it when you run "ruby script/server".
LVL 14

Accepted Solution

wesgarrison earned 2000 total points
ID: 26072906
Hey, are you on Snow Leopard?  If so, you're probably having an issue with the 32 vs 64 bit versions of the gems.

Here's a good thread for people with that issue:

You probably need to uninstall the mysql gem, then reinstall it with some additional flags.
LVL 14

Expert Comment

ID: 26072927
One more link to someone explaining this issue:


You'll probably need to specify the path to your MAMP's mysql installation, wherever you put it.

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