Re: Huge difference between sqlplus and sqldeveloper - sorting in memory vs disk
From: Denis <denis.sun_at_yahoo.com>
Date: Tue, 15 Nov 2011 07:51:27 -0800 (PST)
Message-ID: <1321372287.23718.YahooMailNeo_at_web161804.mail.bf1.yahoo.com>
>> it's dangerous when implicit conversion happen.
>> 1. incorrect result, as this example show.
>> 2. performance penalty, if the conversion happen on the index key, the index can't be used and bad execution will be probably generated.
Date: Tue, 15 Nov 2011 07:51:27 -0800 (PST)
Message-ID: <1321372287.23718.YahooMailNeo_at_web161804.mail.bf1.yahoo.com>
>> it's dangerous when implicit conversion happen.
>> 1. incorrect result, as this example show.
>> 2. performance penalty, if the conversion happen on the index key, the index can't be used and bad execution will be probably generated.
Totally agree. However I really cannot cotrol vendor's code. When a 2000+ line sql was given to me for tuning, I overlooked the date string. Now I am happy that I can focus on the real objective.
- Denis
-- http://www.freelists.org/webpage/oracle-lReceived on Tue Nov 15 2011 - 09:51:27 CST