Integration of FreePBX and SugarCRM

Hi everyone,

I’m new to FreePBX, but my boss has asked me to customize FreePBX.
I have two questions:

  1. What’s the difference between the tables users and
    voicemail_users. Is there any relation between these two? What kind of
    relation? one-to-one? one-to-many?

  2. Is it possible to use a prefix for FreePBX tables?

Thank you in advance,