func TestExcept(t *testing.T) {
relationOne := nodes.Relation("table_one")
relationTwo := nodes.Relation("table_two")
relationThree := nodes.Relation("table_three")
one := nodes.SelectStatement(relationOne)
two := nodes.SelectStatement(relationTwo)
three := nodes.SelectStatement(relationThree)
one.Combinator = nodes.Except(one, two)
two.Combinator = nodes.Except(two, three)
expected := `(SELECT FROM "table_one" EXCEPT (SELECT FROM "table_two" EXCEPT SELECT FROM "table_three"))`
if got, _ := sql.Accept(one); expected != got {
t.Errorf("TestUnion was expected to return %s, got %s", expected, got)
}
}
// Except sets the SelectManager's Tree's Combination member to a
// ExceptNode of itself and the parameter `manager`'s Tree.
func (self *SelectManager) Except(manager *SelectManager) *SelectManager {
self.Tree.Combinator = nodes.Except(self.Tree, manager.Tree)
return self
}