On Wed, 17 Oct 2001 17:17:44 METDST
Haller Christoph wrote:
> I use the second table to identify the actual resp. obsolete ones within the first table.
>
> DELETE FROM advncd_tempreftime;
> INSERT INTO advncd_tempreftime
> SELECT timepoint,mid,lid,sid,MAX(entrancetime) FROM advncd_onfvalue
> GROUP BY timepoint,mid,lid,sid ;
>
> SELECT o.sid,o.timepoint,o.lid,o.mid,o.value FROM advncd_onfvalue o
> WHERE EXISTS
> (SELECT * FROM advncd_tempreftime t WHERE
> o.timepoint = t.timepoint AND
> o.mid = t.mid AND
> o.lid = t.lid AND
> o.sid = t.sid AND
> o.entrancetime = t.entrancetime
> ) ;
Hi,
It seems that a series of the operations can be unified.
SELECT o.sid,o.timepoint,o.lid,o.mid,o.value FROM advncd_onfvalue as o WHERE EXISTS (SELECT t.timepoint,
t.mid,t.lid, t.sid FROM advncd_onfvalue as t GROUP BY t.timepoint, t.mid, t.lid, t.sid
HAVINGo.timepoint = t.timepoint AND o.mid = t.mid AND o.lid
= t.lid AND o.sid = t.sid AND o.entrancetime =
MAX(t.entrancetime) )
;
By the way, a mail server have been downed ?
Regards,
Masaru Sugawara
