Having an entity without columns in your schema, such as:

schema.yml

MyEntity:

results in the following error during doctrine tasks execution:

Warning: array_keys(): The first argument should be an array in /Users/dtyler/Sites/quartz/plugins/sfDoctrinePlugin/lib/doctrine/Doctrine/Import/Schema.php on line 333

Obviously this is a *very* rare edge case, and is more of an annoyance than anything. But it could certainly cause a newcomer confusion and cause them to spend a lot of time trying to fix a problem in their schema that doesn't exist.

Anyone who is running into this problem and want's a workaround, can simply add an empty "columns:" definition the the entity as follows:

schema.yml

MyEntity:
  columns: