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Home -> Community -> Usenet -> c.d.o.misc -> Re: Slight "I have some string, how lng it it, BTW, it's blue" question
Andrew wrote:
> "Brian Peasland" <oracle_dba_at_nospam.peasland.net> wrote in message
> news:J0HyE7.xG_at_igsrsparc2.er.usgs.gov...
>>> : If you use a view and query from the view, you are using a SQL
>>> : Using cursors to do your join will usually be slower than doing it
>>> : a well-formed SQL statement. >>> >>> can you expand on what you mean by 'Using cursors to do your join'? are
>>> really indicating using more than one SQL statement and somehow
>>> the join programmatically? after all a 'join' is by definition down
>>> SQL statement which is run within a cursor -- so what am i missing here? >> You'd have to ask the OP. It was he who said "Sorry it this isn't clear >> - the reasoning behind >> some of the use of cursors to mimic joins is way beyond me." I'm >> assuming that he is processing >> the join programmatically, but that is just an assumption. >> >> Cheers, >> Brian >>
As well you should be. As I stated before....if you can do it in SQL, choose that approach over PL/SQL. Most every time, SQL will beat PL/SQL. I cannot think of an exception to this rule, but I'm leaving open the possibility that someone will come up with that exception.
> OK - if you get paid, you do what you're told - but #i consider it to be a
> personal affront - and would like ammo to try and change it. Hell - our
> hardware supplier must be making a fortune we should not be paying on the
> back of this approach.
> Even more than SQLServer on NT - I'd expect huge gains with cunning ( or
> totally bleeding obvious) use of the parallism you can get by splitting
> queries over several views. Seems a no brainer to me - but apparently I'm
> wrong.
>
Oracle will merge views by default. So if you have a view call a view, and your write SQL to reference the first view, Oracle will merge all the views into your SQL statement and then execute the entire thing as one large SQL statement.
HTH,
Brian
-- =================================================================== Brian Peasland oracle_dba_at_nospam.peasland.net http://www.peasland.net Remove the "nospam." from the email address to email me. "I can give it to you cheap, quick, and good. Now pick two out of the three" - UnknownReceived on Thu Jun 08 2006 - 08:32:08 CDT