Re: Wow - has anyone used ROW_NUMBER() to get around using a UNION statement when UNION ALL doesn't work??

  • From: "Taylor, Chris David" <ChrisDavid.Taylor@xxxxxxxxxxxxxxx>
  • To: Dominic Brooks <dombrooks@xxxxxxxxxxx>
  • Date: Sat, 6 Aug 2011 07:17:26 -0500

Again, I'm not trying to solve a problem.  I'm curious if anyone has used 
row_number to get around using an UNION (when a UNION ALL is not an acceptable 
replacement).  And correlated to that if anyone wanted to discuss the pros and 
cons.

Sent from my mobile device.  Please ignore any typos or misspellings.

On Aug 6, 2011, at 1:09 AM, "Dominic Brooks" <dombrooks@xxxxxxxxxxx> wrote:

> Are the estimates for the plan accurate?
> This is key to having properly sized workareas, etc.
> 
> See Randolf's post on hash aggregation and workareas:
> http://oracle-randolf.blogspot.com/2011/01/hash-aggregation.html
> 
> > From: ChrisDavid.Taylor@xxxxxxxxxxxxxxx
> > To: greg@xxxxxxxxxxxxxxxxxx
> > CC: oracle-l@xxxxxxxxxxxxx
> > Date: Fri, 5 Aug 2011 18:50:57 -0500
> > Subject: Re: Wow - has anyone used ROW_NUMBER() to get around using a UNION 
> > statement when UNION ALL doesn't work??
> > 
> > Greg, I didn't want to include all that in a general discussion on the 
> > list. I've got the plans, trace files and the tkprof outputs. 
> > 
> > I wanted to gauge interest primarily.  Wolfgang, as an example, asked about 
> > HASH GROUP BYs. I'm not trying to solve a problem as much as discuss an 
> > interesting idea. So I wasn't sure what people might want to see AND not 
> > see.
> > 
> > 
> > 
> > Sent from my mobile device. Please ignore any typos or misspellings.
> > 
> > On Aug 5, 2011, at 3:40 PM, "Greg Rahn" <greg@xxxxxxxxxxxxxxxxxx> wrote:
> > 
> > > It would be extremely useful when talking about different plans to
> > > actually have the output from dbms_xplan.display.
> > > 
> > > On Fri, Aug 5, 2011 at 1:15 PM, Taylor, Chris David
> > > <ChrisDavid.Taylor@xxxxxxxxxxxxxxx> wrote:
> > >> 
> > >> Doh!
> > > 
> > > 
> > > --
> > > Regards,
> > > Greg Rahn
> > > http://structureddata.org
> > > 
> > 
> > --
> > //www.freelists.org/webpage/oracle-l
> > 
> > 

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