[ams6110]

Agreed, if the data are from a database table, it's likely that all the tables in the database were exposed. Depends on the method of intrusion, e.g. did they get access to a database backup, access to the live database, access to something a developer carelessly left unprotected in EC2, etc.

Also their statement "We have no reason to believe that any other MyHeritage systems were compromised" is a fancy way of saying "we have no idea what happened" and equivalent in my mind to "We have no reason to believe that any other MyHeritage systems were not compromised.