Re: Qualifying columns to improve performance?

From: Connor McDonald <hamcdc_at_yahoo.co.uk>
Date: Tue, 03 Apr 2001 03:25:35 -0700
Message-ID: <F001.002DF58B.20010403031029@fatcity.com>

Why not try the two (one with qualifiers and one without) and trace each - on a freshly started database...

See how much additional recursive sql occurs (if any)

hth
connor

• Arn Klammer <Arn.Klammer_at_austrac.gov.au> wrote: > At a course some years ago, we were told that in
  > join statements, we should qualify ALL our column
  > names with the appropriate table name, not just
  > those that may be ambiguous. The reason was that the
  > parser would not need to spend time checking
  > multiple tables to determine the table to which each
  > column belongs.
  >
  > Is this still a valid rule?
  >
  > Does this apply to statements in PL/SQL
  > procedures/packages? Or are they different, because
  > they are checked at compile time?
  >
  > -a
  >
  >
  >
  

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Connor McDonald
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Received on Tue Apr 03 2001 - 05:25:35 CDT