попытка…
ВЫБЕРИТЕ a.webpage_link_id, a.webpage_id, a.webpage_RSLink1, b.webpage_name, b.webpage_url, a.webpage_RSLink2, c.webpage_name, c.webpage_url
ОТ table1 a
СОЕДИНИТЕ Table2 b НА a.webpage_RSLink1 = b.webpage_id
СОЕДИНИТЕ Table2 c НА a.webpage_RSLink2 = c.webpage_id