472,959 Members | 1,800 Online
Bytes | Software Development & Data Engineering Community
Post Job

Home Posts Topics Members FAQ

Join Bytes to post your question to a community of 472,959 software developers and data experts.

LINQ to SQL - Help with restructuring a query

Hi -

I'm trying to get my head around LINQ to SQL and the new syntax. I have a
query that's working, but I have a feeling that it's not as clean as it could
be. I would like some guidance on how to improve it.

In short, there's a table that can have multiple entries for a single
respondent and I want the record that they entered last (i.e.
MAX(ResponseDate))

In T-SQL, it would look like this:

SELECT [xml] FROM tblRawResults r
WHERE r.RespondentId = 111111
AND r.ResponseDate =
(
SELECT MAX(ResponseDate) FROM tblRawResults r
WHERE r.RespondentId = 111111
)

I have translanted the query to LINQ as follows:

output = db.RawResults.Single
(
r1 =r1.RespondentId == p_RespondentId &&
r1.ResponseDate ==
(
(from r in db.RawResults
where r.RespondentId == p_RespondentId
select r.ResponseDate).Max()
)
).Xml;
I have suspect that there's a way to do this w/o the use of that subquery
that T-SQL requires. Somehow integrating that MAX into the main query. Am I
correct, or is this the proper way to translate it?

Thanks for your input.
--
-Paul Prewett
Apr 8 '08 #1
1 1189
Have you tried hooking the data-context's Log into Console.Out? What
does the TSQL look like?

Marc
Apr 8 '08 #2

This thread has been closed and replies have been disabled. Please start a new discussion.

Similar topics

0
by: Marshal | last post by:
I've just had a chance to review LINQ, DLinq, and XLinq, (which I only heard about last week after the PDC). The various LINQs actually seem to live up to expectations - Using query semantics to...
8
by: Mike Mascari | last post by:
Hello. I have a query like: SELECT big_table.* FROM little_table, big_table WHERE little_table.x = 10 AND little_table.y IN (big_table.y1, big_table.y2); I have indexes on both big_table.y1...
28
by: Marc Gravell | last post by:
In Linq, you can apparently get a meaningful body from and expression's .ToString(); random question - does anybody know if linq also includes a parser? It just seemed it might be a handy way to...
4
by: BeSharp | last post by:
I recently stumbled across a pretty interesting LINQ to SQL question and wonder, whether anybody might have an answer. (I'm doing quite some increasing LINQ evangelism down here in Germany.). ...
8
by: Andy | last post by:
Hi, I'm trying to add a where clause to my query: List<stringtypes = new List<string>(); types.Add( "A" ); types.Add( "B" ); query = query.Where( c =types.Contains( c.Type ) );
0
by: =?Utf-8?B?SHlwZXJjb2Rlcg==?= | last post by:
I'm encountering some strange behavior after deploying a ASP.net 3.5 website to production, i'm unable to reproduce these in my dev environment. This error seems to occur very randomly but it's...
14
by: thj | last post by:
Hi, I was wondering what you guys are using and why? LINQ to SQL or NHibernate? Thanks in advance, Tommy
9
by: Cirene | last post by:
I'm about to begin a brand new, big, ASP.NET project (using 3.5 .net fw), VS 2008. I'm using MySQL as the backend (customer request.) I have absolutely no experience with LINQ and/or the Entity...
2
by: DJRhino | last post by:
Was curious if anyone else was having this same issue or not.... I was just Up/Down graded to windows 11 and now my access combo boxes are not acting right. With win 10 I could start typing...
0
by: Aliciasmith | last post by:
In an age dominated by smartphones, having a mobile app for your business is no longer an option; it's a necessity. Whether you're a startup or an established enterprise, finding the right mobile app...
2
by: giovanniandrean | last post by:
The energy model is structured as follows and uses excel sheets to give input data: 1-Utility.py contains all the functions needed to calculate the variables and other minor things (mentions...
3
NeoPa
by: NeoPa | last post by:
Introduction For this article I'll be using a very simple database which has Form (clsForm) & Report (clsReport) classes that simply handle making the calling Form invisible until the Form, or all...
0
isladogs
by: isladogs | last post by:
The next Access Europe meeting will be on Wednesday 1 Nov 2023 starting at 18:00 UK time (6PM UTC) and finishing at about 19:15 (7.15PM) Please note that the UK and Europe revert to winter time on...
3
by: nia12 | last post by:
Hi there, I am very new to Access so apologies if any of this is obvious/not clear. I am creating a data collection tool for health care employees to complete. It consists of a number of...
0
NeoPa
by: NeoPa | last post by:
Introduction For this article I'll be focusing on the Report (clsReport) class. This simply handles making the calling Form invisible until all of the Reports opened by it have been closed, when it...
0
isladogs
by: isladogs | last post by:
The next online meeting of the Access Europe User Group will be on Wednesday 6 Dec 2023 starting at 18:00 UK time (6PM UTC) and finishing at about 19:15 (7.15PM). In this month's session, Mike...
2
by: GKJR | last post by:
Does anyone have a recommendation to build a standalone application to replace an Access database? I have my bookkeeping software I developed in Access that I would like to make available to other...

By using Bytes.com and it's services, you agree to our Privacy Policy and Terms of Use.

To disable or enable advertisements and analytics tracking please visit the manage ads & tracking page.