Select DataRow With Latest Date Using LINQ/
Jul 23, 2012I have a datatable where there are 3 columns
ID | Name | Date
and i have 4 columns
1 | ABC | 20/07/2012
[code].....
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Select Two Datacolumns From A Datarow In Linq ?
Aug 23, 2010Dim orders = From tt In testTable _
Order By tt.Item("OrderNumber") _
Select tt.Item("OrderNumber"), tt.Item("OrderId")
This is breaking. Is there a way to do this? I would have thought it was easy enough. Obviously, I thought wrong....
Linq To Datarow, Select Multiple Columns As Distinct?
Apr 16, 2010basically i'm trying to reproduce the following mssql query as LINQ
SELECT DISTINCT [TABLENAME], [COLUMNNAME] FROM [DATATABLE]
the closest i've got is
Dim query = (From row As DataRow In ds.Tables("DATATABLE").Rows _
Select row("COLUMNNAME") ,row("TABLENAME").Distinct
when i do the above i get the error
Range variable name can be inferred only from a simple or qualified name with no arguments.
i was sort of expecting it to return a collection that i could then iterate through and perform actions for each entry. maybe a datarow collection?
As a complete LINQ newb, i'm not sure what i'm missing.
i've tried variations on
Select new with { row("COLUMNNAME") ,row("TABLENAME")}
and get:
Anonymous type member name can be inferred only from a simple or qualified name with no arguments.
to get around this i've tried
Dim query = From r In ds.Tables("DATATABLE").AsEnumerable _
Select New String(1) {r("TABLENAME"), r("COLUMNNAME")} Distinct
however it doesn't seem to be doing the distinct thing properly.
Select Only Date Value No Time In LINQ To SQL?
May 17, 2009I need to have a query which list all the user according to the date value in the database. Problems is this, in the database the date format is 5/5/2009 4:30:12 but I want to compare with 5/5/2009. I think the value of the based date is 5/5/2009 12:00:00 and that's why I couldn't query it.
The query is something like
dim db = new databcontext
dim user = from u in db.datacontext where u.signUpTime = 5/5/2009 select u.
Linq : Find Item In DataRow[]?
Sep 28, 2011gefundeneID = drTerminal.AsEnumerable().Single(Function(s) s("TerminalID") = RandomID)Have an array of DataRow and want to look if the RandomID is in one of the rows.What's wrong with this code?
View 2 RepliesValue Of Type 'System.Linq.IQueryable(Of Date?)' Cannot Be Converted To 'Date'
Dec 6, 2011I'm trying to get datetime value but here is issue with nullable datetype.
Public Function GetDate(ByVal kodg As Integer) As DateTime
Dim g = From dt In db.xDates _
Join f In db.xGrafiks On dt.КодД Equals f.DateKod _
[Code]....
Date Time Picker - When Select A Date, The Text Does Not Go Away
Apr 7, 2011The problem that I'm having is that when I try to select a different date, the text doesn't go away. That may make no sence, but let me tell y'all what I've done.
1: Created a GroupBox
2: Put a DateTimePicker in the GroupBox
3: Put TextBoxs in the GroupBox
4: Changed the DateTimePicker to look like this:
A)Checked - False
B)Allow Drop - True
I thought that if I changed that, then the text in the text box would go to that specific date. It didn't do that, it just stays the same. What I'm trying to do is enter text in say 3/7/11 and when I choose date 6/12/12 it will display blank text boxes for me to enter something different.
How To Select Records With The Max Date (highest Date)
Oct 5, 2009I know how to do this in C#, but my dev team doesn't use C#...here is the answer in C#:How do I do this in VB?Essentially, if I knew how to write lambda expressions in VB, I would be set, but the materials I hav
View 2 RepliesAsp.net - LINQ To SQL - Select SUM With A WHERE?
Aug 17, 2009I'm having trouble getting a Linq to Sql query to work. Basically, I want the sum of a column in a table for only rows matching a certain condition. A simplified version is this:
Orders = order that contains products
OrderProducts = relational table containing products that are in an order
Products = table containing information about products
I can get the total sum of the qty of products like this:
Dim totalQty = requests.Sum(Function(p) p.OrderProducts.Sum(Function(q) CType(q.ProductQty, Nullable(Of Integer))))
(Requests is a IQueryable of Orders)But I also need to get the sum of qty where the actual product meets a certain condition. Something like...
Dim totalQty = requests.Sum(Function(p) p.OrderProducts.Sum(Function(q) CType(q.ProductQty, Nullable(Of Integer))))... WHERE p.OrderProducts.Product.ProductAttribute = true
How would I go about getting that query with the additional where clause to only get the sum of the qtys where the productAttribute = true ?
Linq To SQL Sub Select?
Oct 12, 2009I have the following query which groups some records and then filters where the count of the grouped records is 1.
I'd like to take the returned result and perform another query to retrieve the entire record from the JobcodesWorkingRollup table where the ParentNode column equals the result of this query:
Dim query = From r In context.GetTable(Of JobcodesWorkingRollup)() _
Group r By r.ParentNode Into g = Group _
Where g.Count = 1 _
Select New With {.cnt = g.Count, .nm = g.FirstOrDefault.ParentNode}
Asp.net - Linq Select Compound From
Apr 16, 2009I'm experimenting with linq compount selects. I find the following query not to return any element:
Dim q = From s In d.GetChildRows("DossierSinistri") _
From i In s.GetChildRows("DossierIncarichi") _
Select s
[Code].....
Asp.net Mvc - Why Can't Get Anything Back When Use Linq To Sql Select
Feb 3, 2011Why can't I get any values back when I use Linq to Sql? BHS_TimeSheet is my database table in which have some records. Model.TimeSheet is a class I create in the model. Private db As DataFactoryDataContext
[Code]...
C# - Linq Ambiguity On Where And Select
Nov 15, 2011Today I ran into an issue with LINQ to objects (not SQL) that popped up due to a typo. I had a .Select one place and a .Where in another place. I was expecting same result but they are showing different numbers. Assume somelist has 10 elements with all elements having qty = 0
[Code]...
LINQ Select In .NET And C# Differences?
Mar 16, 2011When using VB.NET I can do the following:
Public Function GetUser(ByVal ID as Integer) As User
Dim dc As New YesEntities()
Return (From u in dc.Users Where u.ID = ID).Single()
End Function
And on my .aspx/.vbhtml page I can access the user's department name like this:
Dim DepartmentName as String = new User().GetUser(12).Department.Name
[Code]...
Select Controls Using LINQ?
Jul 25, 2010i try to select controls using LINQ but it show error
here is the code:
Dim testcontrol As VariantType
testcontrol = From cControl As Control In Me.Controls.OfType(PictureBox) Select cControl Order By Name Ascending
[Code].....
[2008] Using Select With Linq
Jan 9, 2009I have seen different examples in Linq and one used Select and another didnt but both return the same results. Is there a reason why we should use Select ?
[Code]...
.net - Linq To Object - Select Distinct
Mar 18, 2010I can't quite figure out why this Linq Statement isn't working as i would expect:
[Code]....
I would assume that this would create a new collection of anonymous types, that would be distinct. Instead it creates a collection the size of the "ThisParentCollection" with duplicate "MyAnonymousType" in it (duplicate id's).
C# - Linq Select Certain Properties Into Another Object?
May 28, 2009So say I have a collection of Bloops
Class Bloop
Public FirstName
Public LastName
[Code]....
Is it possible using Linq to select the FirstName and LastName out of all the Bloops in the collection of Bloops and return a collection of Razzies? Or am i limited to a For-Loop to do my work?
To clear up any confusion, either VB or C# will do. Also this will probably lead to me asking the question of (What about using a "Where" clause).
C# - Select` And `sub` Have Brackets Around Them In VB Linq Expressions?
Jul 12, 2011I converted the following query from C#:
src.Select((c, i) => src.Substring(i)).Count(sub => sub.StartsWith(target))
To the VB.NET query:
src.[Select](Function(c, i) src.Substring(i)).Count(Function([sub]) [sub].StartsWith(target))
Using Developer Fusion. I was just wondering why the VB.NET version has [] throughout.
LINQ / Select Distinct From Dataset?
Aug 20, 2010I have a single columned datatable inside a single tabled dataset.I just want to convert this dataset to distinct rows. Here is my code, it gives compile error '.' expected.
Dim query = _
From email In ds.Tables(0) _
Select email.Field<string>("Email").Distinct()
EDIT: I changed to (Of String) and it works... BUT NOW 'query' is an ienumerable collection of characters... not a datatable... so how do I convert back easily without manually doing a loop?
Linq To SQL Query To Select Maximum Value
Jun 21, 2010Linq to SQL query to Select the maximum "MeanWindSpeed" value? The database name is "WeatherArchives" The TableName is "TblValues" The Column is "MeanWindSpeed" And Also, I would like to have a query to get me the Max "MeanWindSpeed" in each year,
View 1 RepliesSelect Distinct In Linq Query?
Jan 4, 2012I've a collection with the data like this.[code]...
how can select the distinct data using linq?
Select More Than One Column In A Linq Query?
Nov 2, 2009Dim MyQuery = From c In xdoc.Descendants() _
Where c.Attribute(OriginY) IsNot Nothing _
Order By Val(c.Attribute(OriginY).Value), Val(c.Attribute(OriginX).Value) _
Select c.Attribute(UniStr)
Right above you can see my First! linq attempt! And here comes my first question.
How can i select more than one column in a linq query in vb.net?
For example... Select c.Attribute(UniStr) AND c.Attribute(OriginY)
Use If Statement During Select From Linq To Datasets?
Dec 14, 2009I have this LINQ statement [code]...
Is there any way that I can use if/iif within select ?
Use Linq For Select Distinct Values?
Mar 28, 2012I'm pretty new in Linq and the first problem I've is to select the Distinct values from a ObservableCollection( Of T)
I've tried with[code]...
.net - Linq To SQL: Asking If A Date Is Empty?
Jan 13, 2009I've got a new instance of an object in a Linq DBML, but don't know of the test if the a date field is empty.I have tried:
If d Is Nothing OrElse IsDBNull(d) OrElse d <= Date.MinValue Then
TextValue = "nada"
Else
TextValue = FormatDateTime(d)
End If
But the result is "12:00:00 am"
edit: Changed variable name the d
edit: note that the SQL field is nullable
Show Only Date Using Linq?
Nov 9, 2009i want to show only date in my dropdownlist from the database using linq in vb.net...
but everytime the "time" comes too..how to show only date using linq..
.net - Reset Index In LINQ Select Clause?
Mar 13, 2012My LINQ query:
Dim groupedData = (From p In pData _
Group By p.TruncParam Into Group) _
.SelectMany(Function(g) g.Group) _
.Select(Function(d, idx) New With { _
[Code]...
When the TruncParam changes, I would like the index (idx) in the Select clause to reset to 1. So, in the list above, the Index should be SOLUB0001, SOLUB0002, INSOL0001, INSOL0002...CLRES0001, SUMCA0001, SUME0001.
How should I alter the LINQ query?
C# - Get Access To An Incrementing Integer During LINQ Select
Dec 1, 2009[Code]...
I am trying to replace tasks.IndexOf(t) + 1 with something a little simpler. Is there any built in functionality for this? Hrmm xml literals do not seem to translate well on here....
C# - LINQ - Select All In Parent-child Heirarchy
Mar 12, 2012I was wondering if there is a neat way do to this, that DOESN'T use any kind of while loop or similar, preferably that would run against Linq to Entities as a single SQL round-trip, and also against Linq To Objects. I have an entity - Forum - that has a parent-child relationship going on. That is, a Forum may (or in the case of the top level, may not) have a ParentForum, and may have many ChildForums. A Forum then contains many Posts.
What I'm after here is a way to get all the Posts from a tree of Forums - i.e. the Forum in question, and all it's children, grandchildren etc. I don't know in advance how many sub-levels the Forum in question may have. (Note - I know this example isn't necessarily a valuble use case, but the Forum object model one is one that is familar to most people, and so serves as a generic and accessible premise rather than my actual domain model.)