Join Query using Entity FrameWork

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I trying to select user record using

SQL

var customUser = (from u in context.Users
            join pr in context.PasswordRecoveries on u.Id equals pr.userId
            where pr.url == token && pr.requestDateTime.AddHours(12) <DateTime.Now
            select u).First();

Whats wrong in this query?
Please Help me.

Posted 11-Oct-13 2:29am

Vi(ky

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[no name] 11-Oct-13 8:30am

What is the problem u are facing...??

Simon_Whale 11-Oct-13 10:10am

You need to explain this more as technically there is nothing wrong with the query on its own.

Member 12119093 18-Jan-19 12:25pm

Here is https://www.tektutorialshub.com/linq-to-entities/join-query-entity-framework/ you can refer to

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Christian Graus · Answer 1 · 2013-11-07T22:12:00

You need to tell us what errors you get, but EF does not like functions inside it. Do this instead:

XML

DateTime dt = DateTime.Now.AddHours(-12);

var customUser = (from u in context.Users
            join pr in context.PasswordRecoveries on u.Id equals pr.userId
            where pr.url == token && pr.requestDateTime < dt
            select u).First()

Then if it still does not work, tell us what error you get, so we can help you further.

You can also use FirstOrDefault() if it won't always find a value. You should also use an order by if you're using 'first' and there could be more than one record, or the one you get will be essentially random.

DotNet WeblineIndia · Answer 2 · 2014-04-11T20:44:00

C#

//Set date out of query to compare
DateTime DateToCompare = DateTime.Now.AddHours(-12);

//Use FirstOrDefault(), it will return null value or only one record based on data
var customUser = (from u in context.Users
                join pr in context.PasswordRecoveries on u.Id equals pr.userId
                where pr.url == token && pr.requestDateTime < DateToCompare 
                select u).FirstOrDefault();
if(customUser != null)
{
//Success code
}

Code Help 2014 · Answer 3 · 2014-05-26T19:57:00

I would suggest that use sql statements in the form of stored procedures. It will give you better performance. Another point is that its always easy to troubleshoot sql statements than linq statements.

For step by step instructions on how to use stored procedures in entity framework, check this article:

How to use Stored Procedures in Entity Framework[^]

Join Query using Entity FrameWork

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