Comments on: Update Error http://jonathanlewis.wordpress.com/2012/12/07/update-error/ Just another Oracle weblog Tue, 18 Jun 2013 17:11:36 +0000 hourly 1 http://wordpress.com/ By: Sayan Malakshinov http://jonathanlewis.wordpress.com/2012/12/07/update-error/#comment-51896 Fri, 07 Dec 2012 18:20:24 +0000 http://jonathanlewis.wordpress.com/?p=9956#comment-51896 Ooops, sorry my mistake. There are more than 20 subquery executions(I was confused by 40 starts AFTER filter), so scalar subquery caching couldn’t affect.

]]> By: Sayan Malakshinov http://jonathanlewis.wordpress.com/2012/12/07/update-error/#comment-51894 Fri, 07 Dec 2012 17:52:38 +0000 http://jonathanlewis.wordpress.com/?p=9956#comment-51894 Sorry, i don’t understand: if there are 20 rows (it is less than 200), so why there was no effect of scalar subquery caching after restart? AFAIK it’s most often “write consistency” problem with scalar subqueries after minirollbacks with restarts.

PS. Recently was interesting question on our russian forum ( http://www.sql.ru/forum/actualthread.aspx?tid=988126&mid=13574719 ):
How to optimize this query:

UPDATE scott.emp
   SET sal = (SELECT AVG (sal) FROM  scott.emp)
 WHERE sal< (SELECT AVG (sal) FROM  scott.emp)
]]>