Oracle FAQ Your Portal to the Oracle Knowledge Grid
HOME | ASK QUESTION | ADD INFO | SEARCH | E-MAIL US
 

Home -> Community -> Usenet -> c.d.o.tools -> Re: explain plan question

Re: explain plan question

From: Jonathan Lewis <jonathan_at_jlcomp.demon.co.uk>
Date: Thu, 25 Jan 2001 21:30:20 -0000
Message-ID: <980458206.20451.0.nnrp-13.9e984b29@news.demon.co.uk>

Filter covers a multitude of sins, and one of them is a nested loop approach. In this case I think your analysis is correct.

--

Jonathan Lewis
Yet another Oracle-related web site: http://www.jlcomp.demon.co.uk

Practical Oracle 8i: Building Efficient Databases

Publishers: Addison-Wesley
More reviews at: http://www.jlcomp.demon.co.uk/book_rev.html

doug edmunds wrote in message <3a70705e_2_at_news.pacifier.com>... Given this:

Execution Plan


   0 SELECT STATEMENT Optimizer=CHOOSE    1 0 SORT (UNIQUE)

   2    1     FILTER
   3    2       TABLE ACCESS (FULL) OF 'PURCHASE_RECORD'
   4    2       SORT (AGGREGATE)
   5    4         TABLE ACCESS (FULL) OF 'PURCHASE_RECORD'

and if you don't know the query, what kind of information does this give you?
Is this saying that if purchase_record has 1000 rows, that the table will be scanned 1000 times (line 5), once for each row in line 3?

Received on Thu Jan 25 2001 - 15:30:20 CST

Original text of this message

HOME | ASK QUESTION | ADD INFO | SEARCH | E-MAIL US