Hello Leonard

I would not advise trying to delete properties directly in SQL, I would advise using the API. Something like the following (I wrote this in comment so cannot guarantee this will work):

//Get all the pageTypes
foreach (var pagetype in PageType.List())
{
  // Loop through all properties
  foreach (var pageDefinition in pagetype.Definitions)
  {
    if (pageDefinition.Name == "PropertyName")
      pageDefinition.Delete();
  }
}

David

As David said doing it in SQL isn't a prefered way but if your a lone cowboy and want to take the road less travelled I would advice to having sql profiler running and then delete a property in adminmode. This will give you the sp:s used for the command.

Oh.. and yea.. you know.. take a backup =)

Thanks your replies! 

David, I took your advice and deleted the properties with the API. Your code run flawless!