SELECT table1.id1, table1.id2 FROM table2 LEFT JOIN table1 on table1.id1 = table2.id1 and table1.id2 = table2.id2
WHERE table2.enabled = true
Table2Model.
joins("LEFT JOIN table1 on table1.id1 = table2.id1 and table1.id2 = table2.id2").
# и т.д.