var fk = ...;

fk.select(function(it){
	// fk 안에서 모든 column-reference 들을 얻음.
	return it.get("type") == "column-reference";
}).each(function(it){
	// 각 column-reference에서 parent-column을 얻음.
	var childColumn = it.get("child-parent");
});

Foreign key, which defines the relationship, is composed of column-references containing parent column and child column respectively. This attribute obtains these column references from FK and uses them to get the parent column.

var fk = ...;

fk.select(function(it){
	// Get all the column-reference in fk.
	return it.get("type") == "column-reference";
}).each(function(it){
	// Get the parent-column column-reference in each.
	var childColumn = it.get("child-parent");
});