PHP Symfony SQL查询按钮缺少工具栏

Hi am I am using Symfony to develop the Jobeet website while I try to learn it for a bigger project and it is going resonably well so far.

However I have just got to page 73 where it mentiones clicking on the SQL Query button to debug your queries generated, I don't seem to have this button, even on pages that are definately using SQL.

Databases.yml

all:
  propel:
    class: sfPropelDatabase
    param:
      dsn: 'mysql:host=localhost;dbname=jobeet;'
      username: root
      password: password
      encoding: utf8  

Does anyone know why it wouldn't be showing up?

Is there any more information I can provide to help?

If I am not mistaken, you need something like this:

File: config/databases.yml

dev:
  propel:
    param:
      classname:    DebugPDO

Now, if you have web_debug: on in your application settings.yml (for the dev environment), it should work fine.