suffering after the 9i upgrade<\/a> have been reviewed by Oracle Support and the solution is to disable a couple of 9i features<\/p>\n_complex_view_merging=false
_push_join_predicate=false<\/p>\n
I’d had a fairly confident guess at the first (and in fact mentioned it in a comment to the original blog), but I’m glad we got support involved. Both of these settings were part of the optimizer_features_enable change we made.<\/p>\n
[Updated 9th Feb 2006 – I should point out that these two hidden parameters are being set through a login trigger for the particular application user experiencing this problem, based on Oracle’s recommendation. The longer term solution will be to tune specific queries]<\/span><\/p>\n","protected":false},"excerpt":{"rendered":"Just a couple of small updates on some previous blogs. The database that was suffering from network latency problems between it and the app servers was moved down South last week. It all went very smoothly and that particular problem has been resolved. The 20+ hour job runs over night very easily and other areas… Continue reading Updates<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-866","post","type-post","status-publish","format-standard","hentry","category-uncategorized","entry"],"jetpack_featured_media_url":"","jetpack-related-posts":[{"id":868,"url":"http:\/\/orcldoug.com\/blog\/2006\/02\/05\/we-never-learn-do-we\/","url_meta":{"origin":866,"position":0},"title":"We Never Learn, Do We?","date":"February 5, 2006","format":false,"excerpt":"I had an interesting day at work yesterday. We've run into major performance problems when upgrading a number of Production databases from 8i to 9i. How could that happen, when we've performed regression tests to ensure that the applications perform as well as or better than they did on 8i?Probably\u2026","rel":"","context":"With 5 comments","img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":933,"url":"http:\/\/orcldoug.com\/blog\/2005\/10\/17\/ansi-join-syntax\/","url_meta":{"origin":866,"position":1},"title":"ANSI Join Syntax","date":"October 17, 2005","format":false,"excerpt":"A couple of days ago one of my colleagues raised the question - 'ANSI join syntax, does anyone actually use that?' I have pretty strong views on this and so a brief dynamic conversation followed (and that isn't a euphemism for 'stand-up row', I should add!) So, what about ANSI\u2026","rel":"","context":"With 20 comments","img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":1386,"url":"http:\/\/orcldoug.com\/blog\/2008\/02\/27\/optimiser-upgrading-from-9i-to-10g\/","url_meta":{"origin":866,"position":2},"title":"Optimiser – Upgrading from 9i to 10g","date":"February 27, 2008","format":false,"excerpt":"On the one hand, I regret the fact I seem to be posting a lot of links to other people's work at the moment but I couldn't let this one by, if only for those who don't use OraNA or the like and might miss it.The one consistent message I\u2026","rel":"","context":"With 15 comments","img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":1383,"url":"http:\/\/orcldoug.com\/blog\/2008\/02\/24\/reviewing-parameter-files\/","url_meta":{"origin":866,"position":3},"title":"Reviewing Parameter Files","date":"February 24, 2008","format":false,"excerpt":"One of the headline recommendations during the Real World Performance groups presentations at Openworld 2007 was to review your parameter files as part of your upgrade process. It sounds like simple common sense, but they suggested that inappropriate parameter settings that had been implemented during version 7 days for long\u2026","rel":"","context":"Similar post","img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":1071,"url":"http:\/\/orcldoug.com\/blog\/2006\/08\/30\/the-devaluation-of-training\/","url_meta":{"origin":866,"position":4},"title":"The Devaluation of Training","date":"August 30, 2006","format":false,"excerpt":"Howard Rogers has an interesting post on his blog at the moment that is particularly timely from my perspective and that I agree with whole-heartedly. Companies seem increasingly loathe to commit adequate funds and, probably more significantly, staff time to training (although that could be my imagination).Having said that, a\u2026","rel":"","context":"With 20 comments","img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":999,"url":"http:\/\/orcldoug.com\/blog\/2012\/06\/18\/saving-optimiser-stats-9i\/","url_meta":{"origin":866,"position":5},"title":"Saving Optimiser Stats – 9i","date":"June 18, 2012","format":false,"excerpt":"In a recent blog I described how a mis-timed optimiser statistics collection job led to a bad execution plan for one of the SQL statements in a regular batch jobIt's no coincidence that we were already in the process of implementing a change to our stats collection period to retain\u2026","rel":"","context":"With 4 comments","img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]}],"_links":{"self":[{"href":"http:\/\/orcldoug.com\/blog\/wp-json\/wp\/v2\/posts\/866","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/orcldoug.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/orcldoug.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/orcldoug.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/orcldoug.com\/blog\/wp-json\/wp\/v2\/comments?post=866"}],"version-history":[{"count":0,"href":"http:\/\/orcldoug.com\/blog\/wp-json\/wp\/v2\/posts\/866\/revisions"}],"wp:attachment":[{"href":"http:\/\/orcldoug.com\/blog\/wp-json\/wp\/v2\/media?parent=866"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/orcldoug.com\/blog\/wp-json\/wp\/v2\/categories?post=866"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/orcldoug.com\/blog\/wp-json\/wp\/v2\/tags?post=866"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}