CDbException: What does this mean?

Question

This just happened, but just one time. Any idea why?

CDbException

CDbCommand failed to execute the SQL statement: SQLSTATE[HY000]: General error: 2013 Lost connection to MySQL server during query. The SQL statement executed was: SELECT id, groupId, name, handle, context, instructions, translatable, type, settings FROM craft_fields WHERE context = :context ORDER BY name. Bound with :context='global' (/Users/johndoe/Desktop/Projects/websitetest/craft/app/framework/db/CDbCommand.php:543)

0 /Users/johndoe/Desktop/Projects/websitetest/craft/app/framework/db/CDbCommand.php(396): CDbCommand->queryInternal('fetchAll', Array, Array)

... (large, not relevant stack trace)

30 {main}

Answer 1

CDbException is the exception that Yii will throw when something has gone wrong with a database operation.

Here's the only important part of the error message:

SQLSTATE[HY000]: General error: 2013 Lost connection to MySQL server during query.

Unfortunately that error can occur for any one of 3,210 different reasons including network connection errors, misconfigured PDO, MySQL and/or PHP, etc. It's going to be difficult to track down especially if it's only occurring sporadically.

Answer 2

Looks like it is failing in local development on a Mac. My experience with native MySQL on OS X 10.9.3 is that the MySQL server just stops working once every few weeks, and I have to restart it. Since it's only occasional and I don't use it for anything really critical, I just live with the restarts.