I 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.
I 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..
I 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()
I 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].....
Is it possible to select distinct values from a DataTable?
View 5 Repliesi 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 RepliesI 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]....
Like "SELECT DISTINCT(Col)" in sql query, how do we perform this in datagridview?[code]...
View 3 RepliesIm 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 RepliesMY TABLE
sample comment1
sample comment2
[CODE]...
if sample column value is the same, i want all comments value to be concatenated
do while dr.read
listbox1.items.add(dr.getstring(0))
[CODE]...
I 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.
I am using vb.net and WPF. In a wpf window I am showing a datagrid in the load event while in the load event itself, I need to count grand total amount from a single datagrid column and add it to a textbox in same page .
My page looks like this:
My DataGrid:
Item Quantity Total
Shirt 2 200
Pant 1 500
Tie - -
Belt 2 100
My Textbox ---> Grand Total amount : - 800
How do I do that if I am counting from a ((Total Column )) DTG
And adding it and showing it in my (( GRAND TOTAL AMOUNT)) TEXTBOX
I want to loop through a databale and change the values of a specific column in that datatable.eg: the database returns Request_ID, Desc, Date and Status_Ind. The Status_Ind column contains integer values. I dont want to show the integer values to the user. I want to convert that to a string value based on the integer values returned in that columns.
View 2 RepliesI have a datatable contain fId field. I want to update all values for this field to "1" without using loop. [Code]
View 1 RepliesI'm trying to make a method that can get unique values from a specified column of a DataTable. The problem is that the column may be string, integer, etc. I'm not sure what type of variable the (Of T) is.
Private Sub GetColumnUnique(ByVal dbTable As DataTable, ByVal ColumnNumber As Integer, ByVal ColumnType As ???)
Dim results As List(ColumnType) = (From item In dbTable.AsEnumerable Select item.Field(ColumnType)(ColumnNumber)).Distinct.ToList
End Sub
I am trying to populat a treeview with nodes that are the values of a column in a datatable. I have managed to get the correct number of nodes but the text is not displayed next to the nodes, there is just a 3 shape but the other way round and with square corners shown.
The code is below. I would like to have these parent nodes populated on the form load and then (i think this is what i have read) to be quicker i would like to then load the childnodes once a parent node has been selected, as i don't want to load the whole database on form load or when the form is refreshed.
Here is the code with more dtails below:
[Code]...
How can I query a DataTable to find all of the unique values in a column? SQL has the 'unique' or 'distinct' keywords, but I dont know how to do this against a DataTable.
View 6 RepliesI need to Count row with Distinct from Datagridview.
View 2 RepliesI have to perform the following SQL query: select answer_nbr, count(distinct user_nbr)
from tpoll_answer where poll_nbr = 16 group by answer_nbr The LINQ to SQL query
[Code]...
On to my question.I have a List(of String) that contains multiple items in each index.
A list declared as:
Dim NewStrings As New List(Of String)
May contain the following:
item (0) - (1 MKNO ABC 2.45 STND 3.3)
item (1) - (1 MKGO ABC 1.34 STND 2.5)
item (2) - (1 MKNO ABC 2.45 STND 3.3)
item (3) - (1 MKNO ABC 2.45 STND 3.3)
[Code]...
I have a Table:
[Code]...
I'm trying by LINQ-query (VB.NET) to return a count for distinct value of Objects, Stuffs and Colours for every Room:
[Code]...
If 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 RepliesI 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 RepliesI have added a column to a Datatable called CallsPerDay which is there to tell me how many telephone calls have been made on a particular day or days.Is there a datacolumn.expression which will allow me to Filter on the day, count the rows and then populate this added column with the result.
View 1 RepliesI 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?
I 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 RepliesI have a datatable which has 5 column. It is possible to copy only its 2 column in and save it into new datatable.I used this code but it copies all the 5 column
Code:
Dim qry As DataTable = (From obj In temptable Where obj.Item("Column1") = 0 _
Select obj).CopyToDataTable
i used this one but it is not supported
Code:
Dim qry As DataTable = (From obj In temptable Where obj.Item("Column1") = 0 _
Select obj.item("Column1"), obj.item("Column2")).CopyToDataTable
I 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]....
I have a database which need to be assigned into array arr()(), e.g.
arr(0)(0) = aa arr(1)(0) = ab arr(2)(0) = aa
arr(0)(1) = bb arr(1)(1) = ba arr(2)(1) = ba
arr(0)(2) = cc arr(1)(2) = cc arr(2)(2) = cc
I need to find distinct / unique value in each arr(k)(0), arr(k)(1), arr(k)(2); where k=0..2. Then i need to insert the result into array cat as follows:
cat(0)(0) = {aa} cat(0)(1) = {ab}
cat(1)(0) = {bb} cat(1)(1) = {ba}
cat(2)(0) = {cc}
I've tried code below but it doesn't work. The assigning process into array arr()() from DB is OK. Problem only come up if I try to find the distinct value (If Not (cat(j).Contains(ds.Tables(0).Rows(i).Item(j))) ... End If).
For i = 0 To 2
list(i) = New Integer(3) {}
For j = 0 To 2
[Code].....
I have a List(Of Hardware) - the List is called HWModels
Class Hardware has the following Properties:
ModelName
Status
CPUStatus
MemoryStatus
DiskStatus
The List is populated by reading a CSV file, once it's populated, I want to return the distinct records based on the ModelName
I've attempted by doing it as follows:
(From a In HWModels Select a.ModelName).Distinct
But this isn't right because I end up with a list of only the ModelName's and nothing else.
How do I get the Distinct function to return all of the other class members within the list?