April, What can I say? Ouch! I feel your pain. I've been trapped in some pretty ridiculous situations too. (Though, I think you have me beat! A 37 column primary key?? Really??) Well, you at least seem to have the proper attitude. ;-) Without a sense of humor, I'm afraid you'd go insane in short order! ;-)
The only other thing I can think of when people shut you down like that is: document. "At meeting X, on such and such a date, I identified this problem, and Mr. Z told me to not to worry about it." It may not help, but from a sanity point of view, there is a certain amount of satisfaction in "I told you so!", even if you never verbalize it....;-) Hang in there, -Mark On Fri, 2002-10-11 at 08:43, April Wells wrote: > Mark... > > If this were the MOST serious design flaw in the whole mess, I wouldn't care > so much. There is a point where you just shut up (gee, I have been TOLD to > do that in meetings) and wait till it breaks (or worse, one of our clients > buys it and we have to TRY to implement). I am the funny one... the one to > laugh at and make fun of because I keep trying to tell them that you can't > do things. You can't have a totally denormalized Oracle table if there 1500 > columns in it... yes queries will fly on a table that can't be built. You > can't have 37 columns in a primary key. Date really isn't an acceptable > name for a column. > > April Wells > Oracle DBA > Keep yourself well oiled with life, laughter, new ideas and action. > Otherwise you will rust out. _Anonymous > > > -----Original Message----- > Sent: Thursday, October 10, 2002 7:34 PM > To: Multiple recipients of list ORACLE-L > > > Hi Dick, > > I have to disagree with you here. Particularly in the case where this > sequence will see any sort of concurrency, from multiple concurrent > sessions accessing it. This is due to the serialization on the SQ > enqueue. This will cause far worse scalability issues than any I/O. > Not that I/O is insignificant, but in this situation, serialization on > the enqueue will be the real showstopper for scalability. > > As to losing the cached values, well, so what? If your design is such > that it's important to have an unbroken contiguous sequence of numbers > with no gaps, then I would argue that is a serious design flaw. Also, > if that's your requirement, then a sequence is not appropriate, since it > can and will end up causing gaps, the first time you roll back a > transaction. > > Finally, as to sequences losing cached values, unless your instance > crashes or does a shutdown abort, Oracle should not loose any sequence > values. > > -Mark > > > > On Thu, 2002-10-10 at 18:18, [EMAIL PROTECTED] wrote: > > Actually there is no IO penalty since Oracle has to treat the sequence > just like > > any table with the old LRU algorithm. I have several sequences with a > cache of > > 0 and they perform as well as those with a cache value. The big > difference is > > when you shut down the database and all of those cached values end up in > the > > trash. > > > > Dick Goulet > > > > ____________________Reply Separator____________________ > > Author: "Yechiel Adar" <[EMAIL PROTECTED]> > > Date: 10/10/2002 1:38 PM > > > > I think that you will have an update to the sequence number EVERY time > instead > > of every 20 times. That's mean I/o for every nextval. > > > > Yechiel Adar > > Mehish > > ----- Original Message ----- > > From: Tim Gorman > > To: Multiple recipients of list ORACLE-L > > Sent: Thursday, October 10, 2002 7:43 PM > > Subject: Re: sequence numbers > > > > > > CACHE 20 is the default, so if you remove the clause, it will have > absolutely > > no impact on performance or anything else... > > > > ...of course, I get the feeling that that wasn't the gist of your > question, > > was it? > > ----- Original Message ----- > > From: April Wells > > To: Multiple recipients of list ORACLE-L > > Sent: Wednesday, October 09, 2002 8:54 AM > > Subject: sequence numbers > > > > > > I have been given create scripts for sequences to be used in tables > that > > will be loaded via bulk loads. How huge is the potential performance hit > if I > > take out the cache 20? > > > > April Wells > > Oracle DBA > > There is neither good nor bad, but thinking makes it so. -Shakespeare > > > > > > <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> > > <HTML><HEAD> > > <META content="text/html; charset=iso-8859-1" http-equiv=Content-Type> > > <META content="MSHTML 5.00.2314.1000" name=GENERATOR> > > <STYLE></STYLE> > > </HEAD> > > <BODY bgColor=#ffffff > > style="FONT: 10pt Times New Roman; MARGIN-LEFT: 2px; MARGIN-TOP: 2px"> > > <DIV><FONT face=Arial size=3>I think that you will have an update to the > > sequence number EVERY time instead of every 20 times. That's mean I/o for > every > > nextval.</FONT></DIV> > > <DIV> </DIV> > > <DIV>Yechiel Adar<BR>Mehish</DIV> > > <BLOCKQUOTE dir=ltr > > style="BORDER-LEFT: #000000 2px solid; MARGIN-LEFT: 5px; MARGIN-RIGHT: > 0px; > > PADDING-LEFT: 5px; PADDING-RIGHT: 0px"> > > <DIV style="FONT: 10pt arial">----- Original Message ----- </DIV> > > <DIV > > style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: > black"><B>From:</B> > > <A href="mailto:Tim@;SageLogix.com" [EMAIL PROTECTED]>Tim > Gorman</A> > > </DIV> > > <DIV style="FONT: 10pt arial"><B>To:</B> <A > href="mailto:ORACLE-L@;fatcity.com" > > > > [EMAIL PROTECTED]>Multiple recipients of list ORACLE-L</A> > </DIV> > > <DIV style="FONT: 10pt arial"><B>Sent:</B> Thursday, October 10, 2002 > 7:43 > > PM</DIV> > > <DIV style="FONT: 10pt arial"><B>Subject:</B> Re: sequence numbers</DIV> > > <DIV><BR></DIV> > > <DIV><FONT face=Arial>CACHE 20 is the default, so if you remove the > clause, it > > > > will have absolutely no impact on performance or anything > else...</FONT></DIV> > > <DIV><FONT face=Arial></FONT> </DIV> > > <DIV><FONT face=Arial>...of course, I get the feeling that that wasn't > the > > gist of your question, was it?</FONT></DIV> > > <BLOCKQUOTE dir=ltr > > style="BORDER-LEFT: #000000 2px solid; MARGIN-LEFT: 5px; MARGIN-RIGHT: > 0px; > > PADDING-LEFT: 5px; PADDING-RIGHT: 0px"> > > <DIV style="FONT: 10pt arial">----- Original Message ----- </DIV> > > <DIV > > style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: > > black"><B>From:</B> > > <A href="mailto:awells@;csedge.com" [EMAIL PROTECTED]>April > Wells</A> > > </DIV> > > <DIV style="FONT: 10pt arial"><B>To:</B> <A > > href="mailto:ORACLE-L@;fatcity.com" [EMAIL PROTECTED]>Multiple > > > recipients of list ORACLE-L</A> </DIV> > > <DIV style="FONT: 10pt arial"><B>Sent:</B> Wednesday, October 09, 2002 > 8:54 > > AM</DIV> > > <DIV style="FONT: 10pt arial"><B>Subject:</B> sequence numbers</DIV> > > <DIV><BR></DIV> > > <DIV><SPAN class=841194713-09102002>I have been given create scripts > for > > sequences to be used in tables that will be loaded via bulk > loads. How > > > > huge is the potential performance hit if I take out the cache > > 20?</SPAN></DIV> > > <DIV> </DIV> > > <P><FONT face="Courier New">April Wells</FONT> <BR><FONT > > face="Courier New">Oracle DBA </FONT><BR><SPAN > > class=841194713-09102002><FONT face="Courier New">T<SPAN > > class=841194713-09102002>here is neither good nor bad, but thinking > makes it > > > > so. > > > -Shakespeare</SPAN></FONT></SPAN></P></BLOCKQUOTE></BLOCKQUOTE></BODY></HTML > > > > -- -- Mark J. Bobak Oracle DBA [EMAIL PROTECTED] "It is not enough to have a good mind. The main thing is to use it well." -- Rene Descartes -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: Mark J. 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