CDbExpression itself won’t connect to database and won’t fetch any data. Its role is only to ensure that the expression it holds will not be escaped in the generated SQL.
You can find some information about its usage here.
this works, however it doesn’t seem to be a great solution since it involves saving and refreshing and I think this will trigger validation, which I don’t want at this stage, This happens when a form is loaded.
I found that I am more confident with just pulling the current date out of the database server using