in-line view

From: Cobra__77 <Cobra__77_at_hotmail.com>
Date: 2000/07/05
Message-ID: <8wE85.8268$Tb7.51762@news-server.bigpond.net.au>#1/1

If I use in-lines views....and then join those views later in the where clause...will oracle create the inline view once for each join...or just once for all joins....ie perform the joins and store data for that view in memory....

eg

select a.x, b.y, c.z
from (select id,x

      from tab1
      where id > 100) a,


      (select id,y

       from tab2
       where id > 1000) b,


      (select id,z

       from tab3
       where id > 30) c

where a.id = b.id and a.id = c.id

for the above joins will oracle just create 'a' once and store data in memory and then use it for both joins... a.id = b.id and a.id = c.id ...or create 'a' twice ...for both joins...to do a.id = b.id and do the other part a.id = c.id .... Please remember that the above example is very simplified....my query is very very complex than the above...and I have tables with more than 1000000 rows...in each in-line views...so determining this will help me a lot in tuning my queries.....

any suggestions.... Received on Wed Jul 05 2000 - 00:00:00 CDT