Data compare on insert problem

[LKBrwn_DBA]

You may need two statements:

UPDATE tablea a
   SET processed = 'Not processed: already exists'
 WHERE EXISTS (SELECT '?'
                 FROM tableb b
                WHERE b.recordid = a.recordid);

INSERT INTO tableb
   SELECT a.recordid, a.recordtag, SYSDATE
     FROM tablea a
    WHERE NOT EXISTS (SELECT '?'
                        FROM tableb b
                       WHERE b.recordid = a.recordid);