How to create a OneToMany relation?

I have two tables. First must contain a field with many unique (e.g non-repeating) references to second. How can I do that? Seems like Link is a OneToOne relationship, and Table-type field could be nice except that would be a nested child table (e.g child table inside a child table), and these don’t seem to work correctly ( as per Chaining multiple child tables break UI )

am I right to assume that OneToMany in case of erpnext is Table Multiselect + Link for backwards reference?

doing it the “Table Multiselect + Link” way cause UI to break - suggestions list when you try to add something into the field in model creation, refers to the wrong doctype