I was wondering whether anyone could guide me to docu and code
examples how to create and use a has_and_belongs_to_many relationship
with a joining table where TWO columns are used to identify the
relation to TWO alternative tables.
table 1: mothers [mother_id, name]
table 2: fathers [father_id, name]
table 3: children [child_id, name]
joining table 4: children_parent [child_id, parent_id, parent_type]
'parent type' can be either 'mother' or 'father', and depending on
this, the 'parent_id' links to an entry in either the father or mother
How do you define this in Rails and how do you query it when showing
the child data?
Thanks for any suggestions,