sql injection for new users

[nimasdj]

I prefer to use sql injection rather than datamanger api.

a few questions:

1) in usefield and usetextfield tables, other than userid field, is there any other REQUIRED field that should have a value on injection time?
2) the injected account should be a newbie registered member. so what should be the value for the fields "usergroupid", "membergroupids", "displaygroupid" in user table?
3) in user table what are the REQUIRED value on injection time?

I appreciate your help. I am creating this for someone and I don't have license myself, this is why I posted in pre-sales. hope this is fine for admins and look forward to get help here.