Hi TKabe,
I am sorry for the delay of this reply.
If i understand correctly, your existing user data ( in sql format) is taken from another CMS system and you would like to migrate your existing users into EasySocial. If that is the case, you will first need to migrate your users into Joomla ( com_users ) as EasySocial still rely on Joomla users.
Next, your user data from your existing system. If your user data simply contain the username, fullname and email address, then importing your user data into Joomla already sufficient and your users can already login to EasySocial. However, if your existing system contain custom fields, then you will need to manually insert these data into EasySocial. This will be tricky because you will need to map properly the ES profile, ES custom fields and ES custom fields data for each users. Below are the tables involved for migration user custom fields data.
# for user’s profile
# note, custom fields in EasySocial are tied to user profile type.
jos_social_profiles
jos_social_profiles_maps ( this table store which users are associated to which profile type )
# each user profile has one or more steps
# and custom fields are tied to step.
jos_social_fields_steps
jos_social_fields
jos_social_fields_options ( this table stored the options for fields such as dropdown, radio and etc that has the multiple selection )
jos_social_fields_data ( this is the table that stored the actual user custom field data )
Hope this help and have a nice day!