using min|max in where

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От Ben Carbery
Тема using min|max in where
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Msg-id AANLkTinbg96cBzS+w31o75=wYUmHZxmwUJh4bKQc1Az2@mail.gmail.com
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Ответы Re: using min|max in where  (Bruce Momjian <bruce@momjian.us>)
Список pgsql-sql
Hi, I have some sql like so:<br /><br />SELECT min(date) INTO d FROM interest_rate WHERE m_code = NEW.code;<br />UPDATE
interest_rateSET date = NEW.start_date, rate = NEW.initial_rate WHERE m_code = NEW.code AND date = d;<br /><br />
Actuallythis is pgsql but I don't think that matters.<br /><br />I am wondering if I can make this more compact by
somehowincluding the 'min' function in the WHERE clause, but WITHOUT simply moving the select in there. So not
this..<br/><br />UPDATE interest_rate SET date = NEW.start_date, rate = NEW.initial_rate WHERE m_code = NEW.code AND
date= (SELECT min(date) FROM interest_rate WHERE m_code = NEW.code);<br /><br />This is just an example but I seem to
findthis pattern a lot in my functions.<br /><br />B<br /><br />        <br /> 

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