[felixge]

You can use user defined aggregates in postgres to model state machines. I'm using this technique quite successfully and have been meaning to write a blog post about it.

[sandGorgon]

could you talk a bit more about this ?

i was looking at https://sqlsunday.com/2014/05/25/directed-acyclic-graphs-vs-... https://www.qcode.co.uk/post/73 to learn how others have done it