I am not trying to say that the only way to fetch data is a careful query followed by downloading all results. Only that this is the default (or primary) method and should be so addressed in a scheme to access databases from Scheme.
(There are ways to "protect users from themselves" that we use and they appreciate - like limiting the number of rows returned and suggesting that they refine their request to reduce the amount of data. You can even tell them how much data they requested, ...)
Alex
-----Original Message-----
From:
Anton van Straaten [mailto:anton@appsolutions.com]
Sent: Tuesday,
April 02, 2002 9:43 PM
To: Alex Peake
Cc: Bruce Butterfield;
plt-scheme@fast.cs.utah.edu
Subject: Re: scsh in PLT
Scheme?
> Again, why did you select that particular (sub) set of data? Do you want it
> or do you not?
I know you were replying to Bruce, but I'll hammer my point home anyway: in my example, "you" is the user: if you give the user the ability to query data on a fairly ad-hoc basis, they'll often use it in ways that an experienced developer might not. But it allows them to ultimately get to the end result they want.
You're trying to impose a notion of perfection that has to do with system resources, that has much less to do with getting the job done. The system resource argument only applies when system resources are indeed a problem, not when they're not.
And as Bruce pointed out, often one doesn't control the entire system from end to end, which often necessitates doing things less efficiently than might otherwise be possible. If you're designing a general database API, you might want to avoid precluding easy solutions t o real-world problems.
Anton