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Re: How "deterministic" are EXPLAIN PLAN results?

From: Mikito Harakiri <mikharakiri_at_yahoo.com>
Date: 15 Apr 2003 14:16:04 -0700
Message-ID: <bdf69bdf.0304151316.5c51f541@posting.google.com>


"Jonathan Lewis" <jonathan_at_jlcomp.demon.co.uk> wrote in message news:<b73lh9$qvs$1$8300dec7_at_news.demon.co.uk>...
> There is a hidden parameter that controls
> whether the session level optimizer mode is
> pushed into PL/SQL or not.
>
> Somewhere around 8.1.6/7 its default value
> was changed from false to true

Returning to the original claim "Statement within PL/SQL block may have different plan than the same statement executed directly", there are other cases that support it. For example, bug# 2871645 indicates that view merging might be not applied for recursive SQL. But then, there are so many implementation quirks that makes answering "How deterministic are EXPLAIN PLAN results" impossible.

BTW, your article "Oracle Trousers" in dbazine is hillarious. Received on Tue Apr 15 2003 - 16:16:04 CDT

Original text of this message

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