Re: [Haskelldb-users] Resend: patch for review - SQL functions and parameters

[Justin B. <jgb...@gm...>]

On Fri, Apr 4, 2008 at 8:28 AM, Bjorn Bringert <bj...@br...> wrote:
>  this looks great. How do you substitute in values for parameters in queries?

That's something I didn't look at, but is needed. Since I'm using
haskelldb just to generate SQL I haven't concentrated on the runtime
side.  However, see below ..

>  Here, prepare and queryBind are something along these lines (but more
>  general to support multiple arguments, and with some type class
>  constraints):
>
>  prepare :: Database -> (a -> Query (Rel b)) -> PreparedQuery (a -> Rel b)
>
>  queryBind :: Database -> PreparedQuery (a -> Rel b) -> a -> IO [b]

I like this, and I wonder if Peter's code (mentioned in another
thread) addresses it. I'd be glad to take a shot at unifying the two
approaches, once his patch is in.

In any case, do you think the parameters should show up in the type of
Query (Rel b)? Any ideas how that could look, and how to make sure
queries can still be rendered to SQL w/o runtime values (so I can
still get my SQL w/o having to execute it)?

Justin