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From: "ye, wei" <yw at alabanza dot net>
Subject: Re: Moving to a specific row
Date: Aug 31 2000 6:09PM
Michael Peppler wrote:
> Jeff Greif writes:
> > I wrote this thing (groaning all the while) because the guy doing the web
> > pages complained about how slow it was to throw away many thousands of rows
> > to get at a page of 100 in the middle of a long result set, when the user
> > clicked Next. From a forms-based app, I guess you'd use some kind of browse
> > cursor, but the HTTP environment in this case prevented holding the cursor
> > across multiple web pages. Because there was a user interaction to get each
> > page, efficiency was not a huge concern (at least until hundreds of users
> > start doing it simultaneously). There's an index on the ordering field, so
> > the basic queries are pretty efficient. I'm not sure of the FETCH RELATIVE
> > @offset from the cursor though -- even with a server-side cursor it must be
> > pretty bad.
> The correct way to do this in a set-based envionment is to use the
> unique primary key in the where clause to get the next X rows of a
> So assuming you have an identity column as the primary key, you simply
> remember the last value retrieved for the current page, and when the
> user hits "next" you do a request where the primary key > this value.
But in web page, usually the grid need to be shown sorted by different columns,
sometimes is by the primary key, sometimes not, so where the primary key > this
> Pretty straightforward, and fast.
> > ----- Original Message -----
> > From: "Michael Peppler"
> > To: "SybPerl Discussion List"
> > Sent: Thursday, August 31, 2000 9:38 AM
> > Subject: Re: Moving to a specific row
> > >
> > > brevity>
> > >
> > > Interesting.
> > >
> > > What does the showplan look like for such a request? (ie - is it
> > efficient?)
> > >
> > > (and no, Sybase does not support this syntax)
> Michael Peppler -||- Data Migrations Inc.
> firstname.lastname@example.org -||- http://www.mbay.net/~mpeppler
> Int. Sybase User Group -||- http://www.isug.com
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