I hope the difference between the two will not be that noticeable (I'd
say logically they are the same, only the assembly API is different)
once we implement a master generics-friendly object query that was
discussed on the dev list some time back... But this won't happen
overnight of course...
Andrus
On Feb 21, 2008, at 9:40 PM, Kevin Menard wrote:
Thanks. I'll have to give that a go over the weekend. Unfortunately,
my API structure is centered around SelectQuery and a visitor for
adding
expressions and orderings. Changing the root query type will
require a
few more changes than I was hoping for. At least it'll give me an
excuse to finally play with EJB QL.
--
Kevin Menard
Servprise International, Inc.
Remote reboot & power control for your network
www.servprise.com +1 508.892.3823 x308
-----Original Message-----
From: Andrus Adamchik [mailto:[EMAIL PROTECTED]
Sent: Thursday, February 21, 2008 8:56 AM
To: [email protected]
Subject: Re: Queries based on relationship size
EJBQL query with outer joins should help:
1. select c from Customer c JOIN c.orderHistory
(inner join filters customers with Orders, so this is like a
regular SelectQuery)
2. select c from Customer c LEFT JOIN c.orderHistory d WHERE d is
null
(outer join combined with the WHERE clause should allow fetching
customers with no orders)
Two caveats: we still need to add pagination support per CAY-963; I
may have taken a few _temporary_ shortcuts in the EJBQL parser that
may cause trouble with flattened relationships, so let me know if you
run into problems.
Andrus
On Feb 21, 2008, at 3:05 AM, Kevin Menard wrote:
Greetings,
I'm running into a little difficulty performing a query that I think
comes up often enough that it should be fairly straightforward.
I have a schema similar to the following:
Customer <--- BillingInfo <--- Order
I've mapped the read-only relationship "orderHistory" from Customer
to
Order.
Now I'd like to perform two queries. One for customers with orders
and
one for customers without. I'd rather not filter in the app itself
because I'd like to paginate the result lists.
Is there a way to do this without resulting to an SQLTemplate query?
Thanks,
Kevin
--
Kevin Menard
Servprise International, Inc.
Remote reboot & power control for your network
www.servprise.com +1 508.892.3823 x308
