Venstre sammenføj resultatet med tabel2 sådan her:
select t2."Source", to_char(coalesce(t1."The Ratio",0),'990%') "The Ratio"
from table2 t2 left outer join
(select "Source", 100 * count(*) / sum(count(*)) over () "The Ratio"
from TableA
group by "Source") t1
on t1."Source" = t2."Source";