I think I can, But I read a FAQ form cloud sql page, as follows,
Q. Can I use languages other than Java or Python?
A. Only Java and Python are supported for Google Cloud SQL.
What is it supposed to mean? What are they referring to? Can't I use cloud SQL for my PHP app?
I have another question, (I'm so naive to cloud app engine) I'm developing a PHP application locally, thought of upload it finally to google app engine. Is there any way of doing it locally connect Cloud SQL? So that I could make sure. Otherwise It's hard to update uploaded application thousands of times per day during development. Hope you understood my question.