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Re: [Chicken-users] Re: [ANN] New egg: Object-relation mapper Pandora
From: |
Peter Bex |
Subject: |
Re: [Chicken-users] Re: [ANN] New egg: Object-relation mapper Pandora |
Date: |
Thu, 20 Aug 2009 20:33:00 +0200 |
User-agent: |
Mutt/1.4.2.3i |
On Thu, Aug 20, 2009 at 06:24:27PM +0200, Thomas Chust wrote:
> * A complete usage example has been added to the documentation.
In the example, the 'name' column in the 'Tags' table should be TEXT,
shouldn't it?
There's a problem in the 'match method with Postgres, in the presence of
link slots. If I tweak the example a bit to work under postgres, I get
an error at (pretty-print ((a-post 'in-reply-to*) 'count)) :
Error: (collect-results) ERROR: subquery in FROM must have an alias
HINT: For example, FROM (SELECT ...) [AS] foo.
I can fix it by hand by patching up the table clauses:
#;48> (define r (a-post 'in-reply-to*))
#;49> (r 'table-clauses)
((("(SELECT " "in_reply_to" " AS " "id" " FROM " "Posts" " WHERE " "(" "id" "
= " ? )" ")") 1) (("Posts")))
#;50> (r 'set-table-clauses! '((("(SELECT " "in_reply_to" " AS " "id" " FROM
" "Posts" " WHERE " "(" "id" " = " ? ")" ") AS _foo") 1) (("Posts"))))
((("(SELECT " "in_reply_to" " AS " "id" " FROM " "Posts" " WHERE " "(" "id" "
= " ? ")" ") AS _foo") 1) (("Posts")))
#;51> (r 'count)
0
But you need a sequence generator of some sort because otherwise you'll
get several times the same alias in a query. I don't know how to do
that, off the top of my head.
Cheers,
Peter
--
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