vic wrote:
> I have 2 servers, server a is HP (DSS) and server b is Sun. Now one of the
> applications among these 2 servers is to query server b from server a.
> server a has a user, which has a dblink to connect to server b. The strange
> thing is:
> If I query server a from server b using sqlplus as:
> sql> conn user/password_at_b from server a and run query, e.g.
> sql> select ... from table1 , table2 where.... The elapsed time is 10
> seconds but if I use a user in server b and use its dblink (svra) to run:
> sql > select ... from table1_at_svra , table2_at_svra where.... the elased time is
> 4 minutes.
> The listener.ora for server a has an entry as sdu=32768 and tnsnames.ora in
> server b (hp) has also sdu=32768 as its entry. I set tdu for both the same
> as sdu. It is still the same. Theoritically they should have the same
> response time. Why using sqlplus is faster than using dblink? The dblink
> user is also the same user I connect from server a with sqlplus and the same
> connect string as the using clause in dblink. I couldn't figure out. I
> think it is strange. Does anyone have the same strange experience as mine?
> Has anyone ever tackled this issue and willing to share it with me and
> others?
>
> Thanks in advance.
>
>
It's not strange: using the db-link, Oracle may need to fetch both tables
completely, and will then join (where-clause) on server b. In the first case,
the action happens on server a, only the results are transferred.
--
Gerard H. Pille
(plaats puntjes tussen mijn initialen om te antwoorden)
Received on Thu Jan 01 2004 - 19:20:06 CST
