from dual;
を使用してみてください 、このように:
INSERT ALL
INTO table1
(tid, date, title) values (s_tid, s_date, s_title)
INTO table2
(tid, date, user, note) values (s_tid, s_date, s_user, s_note)
SELECT s_tid, s_date, s_title, s_user, s_note
FROM
(
SELECT
1 s_tid,
'01-JAN-15' s_date,
'title' s_title,
'john' s_user,
'test note' s_note
FROM dual;
)