Date: Sun, 29 Aug 2010 09:16:04 -0500
Reply-To: Wensui Liu <liuwensui@GMAIL.COM>
Sender: "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From: Wensui Liu <liuwensui@GMAIL.COM>
Subject: Re: performance between libname and pass-through
Content-Type: text/plain; charset=ISO-8859-1
very good points, Mike
thanks for sharing!
On Sun, Aug 29, 2010 at 8:20 AM, Michael Davis
> Hello Wensui and other SAS-L Friends,
> I use pass-through almost
> exclusively for two reasons:
> 1. With pass-through, I know
> that my joins will execute on the DBMS (Oracle). With the LIBNAME
> engine, they may but I have no guarantee.
> 2. If I have a
> problem that requires consulting with my DBA friends, I can show them
> pass-through code and get a good answer. If I show them SAS code,
> their eyes glaze over and we don't get anywhere helpful.
> On Sat, August 28, 2010 11:33 pm,
> "Wensui Liu" <liuwensui@GMAIL.COM> wrote:
>> What you mentioned makes perfect sense, since
> what pass-through uses
>> is the native DB sql.
>> I am just curious how libname database interface translates SAS
>> functions to DB functions when processing the data.
>> On Sat, Aug 28, 2010 at 11:28 PM, Joe Matise
> <firstname.lastname@example.org> wrote:
>>> I would think it depends
> on what you're doing. If you are doing joins
>>> such that require a lot of tables accessed, but not pulling
> back a lot
>>> data, then pass through should
> be better by a lot (and is in my
>>> experience). The exception
> to that would be if you're not working with
> ton of data and your local CPU is more powerful than the server...
>>> On Sat, Aug 28,
> 2010 at 10:20 PM, Wensui Liu <email@example.com>
>>>> i've read a sugi paper
> comparing the performance between libname and
> pass-through connecting to DB and really have hard time to believe the
>>>> conclusion that their performances are about the same.
>>>> for a straight pull of raw data from
> tables without using too many
>>>> functions, I guess both
> libname and pass-through might perform
> however, when (complex) functions are used in the query, i
>>>> think pass-through should be faster.
>>>> Any idea or experience?
> Thank you so much for sharing.
>> WenSui Liu
> Michael L. Davis
> Ambler PA