StErMi, as far as I’m concern we are not discussing a gap between two different RDBMSes here but the difference (gap) between using an older framework and switching to Yii with using the same RDBMS. Only this way you can correctly evaluate performance change between frameworks and that’s what this topic started from (though got a bit off-topic by the way! :])
I’m in the same situation with a client project and it never occured to me that Yii could be an alternative to Drupal before I read your post and blog.
I read your experience with Yii and Drupal, i’m analysing CMS and other frameworks for an application I need to develop. At the begining it will be so small and with few users, but in a term of six months I expect huge amount of information and users and i’ll add an e-commerce features.
One thing is that i need the first version faster and not too expensive, what do you think about the learning curve for Yii in relation with cake or rails for example(because i know drupal learning curve is a little high)
The other thing is do you see in your experience, that the performance showed in many places about Yii is constant in time? i mean if my app scale that performace continues so good in relation with other frameworks?