Dropping Roundcube native address book (because carddav works) risky?

==== Required information ====
- iRedMail version: 0.9
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): MYSQL
- Web server (Apache or Nginx): NGINGX
- Linux/BSD distribution name and version: CENTOS 6
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====

Hi,
Now that carddav is working, i think i can drop the roundcubes native address book.
is mysql the only way to drop it? (afraid to do something wrong and mess up the db) quite sensitive.
have pinpointed the contacts table in roundcube. So do i drop the entire contacts ?
afraid to do so. please help me!

thanks
kevin