VS 2010 Select Distinct Values From A DataTable?
Sep 28, 2010Is it possible to select distinct values from a DataTable?
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Select Distinct Rows From Datatable In Linq
Jul 14, 2010I am trying to get distinct rows based on multiple columns (attribute1_name, attribute2_name) and get datarows from datatable using Linq-to-Dataset.[code]How to do thin Linq-to-dataset?
View 3 RepliesC# - How To Get Distinct Values From DataTable In DataSet
Dec 23, 2011I am using strongly typed dataset and have many tables in that. The problem is now I want to filter data from
GetData()
function which has a query like
select * from table_name
How can I filter a particular table and distinct values from it. Also if I try to filter it return all column but rest have null values except the one I asked, so I cannot assign it as a datasource to a datagrid or combobox. How can I do this..
Get Distinct Values And Converting Back Into DataTable?
Mar 14, 2012I have a "result" which is DataTable and I like to get the x distinct values(City) and convert it back to DataTable how do I do this the code below gives me an error
Dim query = (From x In results.AsEnumerable()
Select (x.Field(Of String)("City"))).Distinct().CopyToDataTable()
so what I want is records of distinct cities I can get that but the problem I am having is converting it back to Datable.
Edited:I am using "where" in this statement and it does convert to Table(works fine) but not on "select"
Dim results = (From myRow In ds.Tables(1).AsEnumerable()
Where (myRow.Field(Of String)("xxxx") = xxxx)
Select myRow).Distinct().CopyToDataTable()
Get Row Count Of Distinct Values In A DataTable Column?
Mar 13, 2012I have a DataTable that has several hundred rows.I want to get a row count of distinct values in a particular column.For example, I have a DataTable of Product Orders, but I want to get the number of unique Customers.
I was using this code, but I can't rely on it because my binding source is filtered from time to time.If my binding source has filtered out all rows datatable.DefaultView returns 0 rows.
Linq To DataTable Not Producing Distinct Values?
Oct 19, 2010I have a datatable which has been dynamically generated from FoxPro tables using a UNION Select statement. e.g.SELECT * FROM x UNION SELECT * FROM y UNION SELECT * FROM Z ORDER By v_alue1This produces a datatable with about 100 rows, each containing many fields, one of which is c_olor. From this datatable, I would like to select the distinct colors and then output in a dropdown.I have a public class Color which just has one property which I can then use as the DataTextField and DataValueField for the dropdownlist
Public Class Color
Private _c_olor As String
Public Property c_olor() As String
[code].....
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]...
Asp.net - Select Distinct Rows From A Datatable With Criteria Involving Multiple Columns Using LINQ
Mar 9, 2012I have a datatable as shown in the figure. Let me explain my required based on this image. I have 7 rows of data. The rows 1 and 2 contains columns till UnitSqcNo same. I want only row 3 among the two. In general I want select all the rows with distinct model, unittype, unit and rest with greater CompId. ie the table should look like
View 1 RepliesC# - Get Distinct Rows From Datatable Using Linq (distinct With Mulitiple Columns)
Jul 13, 2010I am trying to distinct on multiple columns and get datarows from datatable. but getting error.
Dim query As IEnumerable(Of DataRow) =
(From row As DataRow In SourceTable.AsEnumerable() _
Select row.Field(Of String)("ColumnName1"),
[Code]....
I want another datatable with distinct row based on given columns from SourceTable.
Loop Datatable And Select Checkboxlist Item Based On The Datatable Field Values
Aug 18, 2011I am trying to display value of the field ("UserID") for every row exists in datatable to checkboxlist(make the checkboxlist item selected).
I used for loop, but only the field value from last row of RoleUsers table is selected in the checkboxlist.
Here is my code
Private Sub DisplayRoleUser()
Dim conn As SqlConnection
Dim cmd As SqlCommand
[Code].....
VS 2010 Sum Distinct Values Of Column
Apr 18, 2012Im having trouble getting the sum of a "Status Column" It is unbound. It has 2 Items "Active and Inactive" I would like to have lblInact.Text to show the total of Inactives of that column.
View 20 Replies[VB 2010] How To DISTINCT Values When Have Multiple ComboBoxes
Dec 8, 2011I f I have 1 combobox then my SQL query will be:
Dim objConnection As New OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source = C:DB.mdb;Jet OLEDB:Database Password=Pass1;")
Dim objdataadapter As New OleDbDataAdapter("SELECT DISTINCT LOCATION FROM Table", objConnection)
Distinct Query For Datatable
Oct 22, 2011If I would connect to database I would run a query like this: "Select distinct Column1, column2 from tablename where somefield=somevalue order by column2". How can I run this query to a datatable? I know .select but that's not enough like dataset.datatable("name").select(filter,short). Still need distinct.
View 2 RepliesWhen Fill A Datatable Can Get Distinct Rows For A Specific Column
Oct 23, 2009i fill a datatable in a typed dataset.. it has cities and states but I want to pull just distinct states and bind it to a control etc.. there is the filter, but i havent found a way to do distinct or group by. got to be a way without adding more datatables and filling them with data thats already there right?
View 1 Replies.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).
Constraint Violation When Using Select Distinct?
Aug 6, 2009I have a problem running a simple query: "select distinct payee from table". This query is set up in the dataset and is called GetAllPayee.My code goes something like:
Dim dtSources as new Datatable
dtSources =
Me.TblExpenseRecordsTableAdapter.GetAllPayee
Upon running I get the error:Failed to enable constraints. One or more rows contain values violating non-null, unique, or foreign-key constraints.The problem is, I haven't set ANY constraints on either the new datatable, or the dataset table (tblExpenseRecords). i.e. there is no primary key etc.
Can someone please help me out with this problem?I have no problems running the query through the wizard where I can view the results successfully.
DataView RowFilter - How To Select Distinct
May 29, 2003Is it possible to select distinct in the rowfilter method?
I have something like:
VB
'Create a data view so we can get each items name
Dim dvwItemNames As New DataView(dtlItems)
dvwItemNames.RowFilter() = "SELECT DISTINCT Name"
This gives me a syntax error exception. I tried just "Distinct Name" but this had the same result. "Name" is the column name. I would rather do it this way then looping through the entire table and putting the name in an array list or something.
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?
Select 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 Distinct Items From A BindingList?
Jun 5, 2010I have set up a class to hold song information - artist, title. I then created another class that containg a BindingList(of clsSong). I use this binding list to create a data object that can be used to create an RDLC report. This all works. Now I am trying to remove duplicates from the binding list so they don't show up twice on the report. I can't figure out how to get a distinct list for my report. [code]...
View 3 RepliesSelect Distinct Not Get Result Wanted
Jul 4, 2011I used the following code to select unique values from the database [code]And it does not retrieve the unique values, it remains the same. But if I use only SELECT DISTINCT Author FROM tblBook it works fine.
View 3 RepliesUse Select Distinct From A Tables Row In MS Access?
Oct 29, 2010I have a form with a list box The code loops through a Tables' row and gives me only one of each of the catergories. If more than one of a perticular item exist it only displays one. i would like to use Select Distinct instead just because it would cut down on the time it would take to read the Rows items and still give me the same results I just am not sure how to write it.
[Code]...
2005 - Unable To Get Distinct Records From Datatable Using DefaultView.ToTable?
Mar 14, 2012I am building a custom search control in VB.NET and came across a problem getting distinct records into my datagridview. I want to bring exact matches back first so I run 2 of the same query on the same table with a slight difference:
select ... like "code%"
select ... like "%code%"
I have a datatable that I need to get distinct records from; I am append records from a sql query to the end of the datatable so I cannot use a union in sql to return the dataset (I want to preserve the order which the rows are added) I have been using this which is working fine for 2 fields:
dt2 = dt.DefaultView.ToTable(True, "Code", "Name")
But when I have 3 (or more) fields I get duplicates ONLY for the row I am querying:
dt2 = dt.DefaultView.ToTable(True, "Code", "Name", "Initial")
select ... like "initial%"
select ... like "%intial%"
I am clearing the datagridview.source before rebuilding this. Is there a way to get the distinct rows this way or should I just build something myself to remove the duplicates from the second datatable before appending them to the new table?
LINQ To SQL Select Distinct From Multiple Colums?
Apr 2, 2010I'm using LINQ to SQL to select some columns from one table. I want to get rid of the duplicate result also.
Dim customer = (From cus In db.Customers Select cus.CustomerId, cus.CustomerName).Distinct
Result:
1 David
2 James
1 David
3 Smith
2 James
5 Joe
Wanted result:
1 David
2 James
3 Smith
5 Joe
Can anyone show me how to get the wanted result?
C# - LINQ Select Distinct While Evaluating Multiple Rows
Jul 11, 2011I have an EnumerableRowCollection that looks like the following:
VendorCode | GroupType | Variance
01165 G .16
01165 G .16
01165 CH .16
01165 CH .18
07754 G .25
07754 G .25
07754 G .39
Essentially, this is a massive list of vendor codes, their groups, and price variances. I need to compose a query that will create a distinct list vendor codes and group types. The catch, however, is that I need to evaluate all of the variances associated with that particular VendorCode/GroupType to see if they are all the same - it they are not, I need to return some way of signifying that the group has a "custom" variance, otherwise it needs to return the value (ie: if they are all .16, then return .16, if there are multiple values, return "custom")
The result would look like this, based off of the list I showed above.
VendorCode | GroupType | Variance
01165 G .16
01165 CH custom
07754 G custom
I have no trouble getting a distinct list of VendorCode/GroupType - this is what I have so far:
Dim distinctList = From q In query Select q.VendorCode, q.GroupType, (evaluated q.Variance here?) Distinct
(where "query" is an EnumerableRowCollection(Of (anonymous type)))
I'm at a loss, though, on how to evaluate the variance property to get the result that I need?
C# - LINQ Select From IEnumerable With Distinct/GroupBy And Sorting?
Oct 19, 2010My particular example is fairly complex but I think the concept would apply equally to something like a logging system so I'll use that instead for ease of explanation. It's a ficticious example, please don't harp on or agonise over what is achitectually, programatically or morally wrong with the example itself
[Code]...
I don't want to 'cheat' and resort to a long-winded way of doing it when performance isn't critical here and I'm moderately confident it can be done in a single LINQ statement.
Finding Distinct Element From Array Before Select Statement?
Nov 8, 2009I have an array with wild character at the end. I use the value in this array in Select statement. Some times the array has same values. I want only distinct values in the array before the select statment.
Code:
for i=0 to count
select * from tbl where item like ' " & itemname(i) & "'
next
I need distinct element in itemname array.
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.
Get Distinct Values In Column 2 Of A DGV?
Aug 9, 2010I am trying to get distinct values in column 2 of a DGV using the following LINQ query:
Dim AllocatedRoomTypes = From r In Me.AllocatedDGV.Columns.Cast(Of DataGridViewCell)() Select r.ColumnIndex = 2 Distinct
but I get the following error:
Unable to cast object of type 'System.Windows.Forms.DataGridViewTextBoxColumn' to type 'System.Windows.Forms.DataGridViewCell'
I understand that the problems lies with the Cast, but I do not know how to correct it.
What I am trying to acheive is this:
Value is Column 2 of DGV
Double
Double
Single
Twin
[Code]....
Asp.net - Generate Columns From Distinct Values?
Oct 25, 2011I have a three column table which lists every person, every event they may have attended, and what percentage of the time they were there. I would really like to display this on one page with the person names on the side and the event names across the top.
Here' an example of what I have:
NAME EVENT %ATTENDANCE
Smith Rock Climbing 50
Allen Rock Climbing 78
[Code]....