appl.dbSynchronize on batch

In Dynamics AX 2009 ...

I need to do appl.dbSynchronize on batch job.

What happens if synchronized doesn't work.

(I think, it is prompted, but since it is a batch job, the job cannot be finished -

Can I eliminate the prompt, and throw it to log file, when running dbsynchronize on batch job?)

What should I do in order to synchronize on batch job?

Thanks :)