Resent-From: POSTGRES mailing list <postman@postgres.Berkeley.EDU>
Resent-Message-Id: <199412151522.HAA12545@nobozo.CS.Berkeley.EDU>
Sender: owner-postman@postgres.Berkeley.EDU
From: kilin@cs.UMD.EDU
Date: Thu, 15 Dec 1994 10:22:34 -0500
Message-Id: <199412151522.KAA05411@twinkie.cs.UMD.EDU>
To: postgres@postgres.Berkeley.EDU
Subject: Question on R-trees
Resent-To: postgres-redist@postgres.Berkeley.EDU
Resent-Date: Thu, 15 Dec 94 07:22:43 -0800
Resent-XMts: smtp


Hi,

Got a couple of questions on R-trees on Postgres:

Suppose I have a relation and index defined as :

create rel1 (code = int4, bound = box)\g
define index rel1ind on rel1 using rtree (bound box_ops)\g

(1) Does it mean that everytime I query using the box operation (like <<, &<
    etc.) the Rtree will be used to access the tuples? Can I force the
    system to use the Rtree?

(2) Will the output be ordered in anyway beacuase of the use of the index?
    I try to run a couple of querys and the output is ordered as the order
    of inputting them. Is it supposed to be that way?

(3) (A dumb question), for the box datatype, is a box constant specified
    by : "(xlow, ylow, xhigh, yhigh)"::box ?

Thanks a lot

David Lin

==============================================================================
   To add/remove yourself to/from the POSTGRES mailing list: send mail with 
   the subject line ADD or DEL to "postgres-request@postgres.Berkeley.EDU".
   If this fails, send mail to "post_questions@postgres.Berkeley.EDU" and
   a human will deal with it.  DO NOT post to the "postgres" mailing list.
==============================================================================
              URL: http://s2k-ftp.CS.Berkeley.EDU:8000/postgres/