ADO.NET :: Linq Query With Ordering?
Jan 28, 2011
the best way to do the following (I'm using a simplified example of my actual problem?Say I have a customer ordered items table with fields: oItemId, OrderId, ProductId, ItemPriceI want to query where OrderId >oMin && OrderId <oMaxand for each value of OrderId I want to find the record with the highest ItemPriceso for a single OrderId the query would be:(from o in context.orderItems where OrderId==x orderby o.ItemPrice select o).first()but OrderId isn't a single value. If I modify the where clause then this query would still produce a single record whereas I want a single record per OrderId.oh and as an additional question: does anyone have a compact test for whether a record exists. I am using the querystring to specify an Id and there are numerous things that I want to protect against. If I do:
var myRecord = from o in context.orders where o.orderId == request.querystring["Order"] select othen this fails if the querystring isn't specified. So first I test that the querystring != nul . Then I need to do:bool recordExists = (myRecord != null)because even if the querystring is specified it may be an invalid orderId and thus the query returns no results. Is there a shorter/simpler way to calculate the result. I have not yet got to grips with lambda expressions and I'm not sure whether there is a better approach with lambda expressions.
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Aug 25, 2010
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[code].....
Now this is fine. However, I now want to sort the ListingImages independently within each Listing (by an ImageOrder column I have in that table).
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Nov 17, 2010
It seem to me that this was hard...
[code].....
I get this run time error "no supported translation to SQL".
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May 28, 2010
I'm looking to translate an SQL query into linq
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Mar 19, 2011
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[code]....
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Jan 22, 2011
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[Code]....
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Aug 2, 2010
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[Code]....
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Mar 11, 2010
Users
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Aug 31, 2010
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[Code]....
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Dec 13, 2010
Table User (UserID, Username)
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someone have an Idea how to solve in 1 query?
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Sep 13, 2010
I have a datakey that I'd like to query from my GridView instead of looping through all the rows and comparing the key of each row. So I was wondering if it was possible to just do a linq query on the gridview (not datatable) and filter with the datakey.
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if (chkMjesto.Checked == true)
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Apr 4, 2011
SELECT Sum(ABS([Minimum Installment])) AS SumOfMonthlyPayments FROM tblAccount
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Mar 15, 2011
This is my code from my controller:
MGEntities db = new MGEntities();
[HttpPost]
public ActionResult Register(RegisterModel model)
{
if (ModelState.IsValid)
{
// Attempt to register the user
MembershipCreateStatus createStatus = MembershipService.CreateUser(model.UserName, model.Password, model.Email);
if (createStatus == MembershipCreateStatus.Success)
{
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Guid UserID = (Guid)myObject.ProviderUserKey;
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profile.Address = model.Address;
profile.City = model.City;
profile.Zip = model.Zip;
profile.State = model.State;
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Debug.Write(profile.State);
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return RedirectToAction("Index", "Home");
}
else
{
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}
}
This is my MyProfile Class:
namespace MatchGaming.Models
{
[Bind(Exclude = "ProfileId")]
public class MyProfile
{
[Key]
[ScaffoldColumn(false)]
public int ProfileId { get; set; }
public Guid UserId { get; set; }
[DisplayName("Address")]
public string Address { get; set; }
[DisplayName("City")]
public string City { get; set; }
[DisplayName("Zip")]
public string Zip { get; set; }
[DisplayName("State")]
public string State { get; set; }
}
}
After the linq query is executed, i check my database and nothing is added. I am using POCO for my entities. Here is my class:
namespace MatchGaming.Models
{
public class MGEntities : DbContext
{
public DbSet<MyProfile> aspnet_Profiles { get; set; }
}
}
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Oct 2, 2010
how convert this sql query in linq,
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Feb 16, 2010
I have a simple query i.e.
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Jan 18, 2010
I've been developing a ASP.NET page and have been using LINQ to handle talking to MS SQL server. I'm ok at basic SQL, however I'm a lot better with designing queries using LINQ. I know they are similar but I find it easer to design complex queries in LINQ. My question is this: Is there a way to design a query in LINQ and then get the SQL that it generated? I would like to embed the SQL in a stored procedure since multiple pages (outside my control) will need to do the same query.
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Feb 4, 2011
my code will explain what the problem is in the WHAT DO I PUT HERE section how can get the list ordered by a-z?
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Feb 19, 2011
i want to oredering My Data In DataTable by DateTime as Desc how???
i know i can do that in sql :
select MyDate from Dates order By Dates.MyDate desc
but i want to order it in DataTable
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