How to tear a DB in two, neatly?

I’m wondering whether someone has a clever idea about how to achieve something ? I have a working, research DB that contains multiple trees. I would like to split it into two, but neatly where neatly means that I can combine the two halves without losing data. If the DB contain two roughly equivalent sized trees this would be easy - I could create a group for each tree and use drag and drop or Gedcom export to separate them. Unfortunately the DB has 300,000 people and maybe 250,000 are in one tree - because of the distant connections between unrelated branches. I could separate the DB based on gender, age, or location but that would mean losing connections when I recombined the two parts.

Has anyone had to solve this problem before and come up with a smart strategy?

Peter

I think the loss of connections is invariably the case when splitting a lineage-linked database and recombining else you end up with duplicates of people. I’m sure many have tried and no-one has a ‘smart strategy’.