Find Out Values In One Datatable That Are Not In Another Datatable?
Dec 28, 2011
I've got two data tables with store numbers. I need to find out what store numbers are in one data table that arent in another.say one table A might look like:
34, 35, 39
the other table B may be
34, 35, 39, 45
I need to find the 45 If I use nested For Next I can get matches but anything not a match would show up not just the 45 value as the next progresses.
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.
I have a datatable and I apply a filter to the defaultview.rowfilter property of that datatable. If I then loop through the rows collection of the datatable, will I only be able to see those rows that the filter applies to, or will it loop through all the rows?
I am working on a project that takes an xml schema and xml data files and places them into a DataTable, the 2 files are generated from a working table that i have written to disk. I wish to load these 2 files into a DataTable. Here is What i have
vb.net Friend Function CreateTable(ByVal tableName As String) As Boolean Dim table As New DataTable(tableName) table.ReadXmlSchema(tableName & ".xsd")
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this however produces the following error on line 3
Quote:
System.ArgumentException was unhandled Message=DataTable 'get_item_list' does not match to any DataTable in source.
get_item_list is the parameter passed into this function (tableName)
I have a datagridview bound to a datatable setting its datasource property to the datatable. I would like to have a child form that contains a list of columns associated with the datatable that contains a checkbox that will allow the user to hide and show the columns ( I do not know the best control to use here) (I assume this is the easy part as All i need to do is loop through each of the datatable's columns to get the column name)
now I would like save these visible columns on some event like form_closing so that the next time the user opens the form up it will remember the settings
I came across a problem with using a BindingSource as my DataGridViews.DataSource. Whenever I applied a filter to a column in the BindingSource and the user makes changes that don't match the column filter the DataGridViewRows would automatically disappear. A similar thing would happen when applying a Sort to a column. If the user made any changes the DridGirdViewRows would automatically sort causing rows to be moved around. This was not ideal for my application and there isn't anyway to stop this from happening with the BindingSource.
To correct this issue I have to use subsets of data. I use a DataView to apply the filter and sort to the main DataTable, which creates the subset DataTable.The problem is when I use the DataView.ToTable method I loose the Primary Key and RowError information. So I have to reapply this information everytime the user filters or sorts the DataGridView.Is there a better way to get a subset DataTable?[code]...
I have a datatable that has a resource in one field and hours used in another, it looks like this -
Resource Hours Used Manager 1 Accountant 1 Field Staff 2 Accountant 3 Manager 4 Manager 1 Administrator 6 Field Staff 4 Manager 0.5 Administrator 1
What I want to do is be able to create a summary of the data table above that groups multiple occurrences of a resource and adds up the hours used for that resource, creating a summary that looks like this -
Resource Hours Used Manager 6.5 Accountant 4 Field Staff 6 Administrator 7
Is there a simple way to assign a populated datatable's columns to another empty datatable? That is, I want to copy a datatable's structure only but not its data.
I'm using vb.net 2010.I have a DataSet with a Table and data. MyDataSet1 which contains Table1 I want to create another table that is the same as the Table1 but without data, but it should have the columns, etc.
Now, I want to place the rows from foundrows into an empty data table.I did what I thought was the obvious but that only returns a bunch of rows with no data
I am trying to add NewRow to the database by using datatable in dataset, but before I do that I want to make sure that row is not already there. I create new row for the datatable I am working with, fill it with information. I fill datatable with the row from database that has the same primary key as my NewRow by using tableadapter.fill method, but when I do that my NewRow that was never added to the datatable is filled with information from database(and not information that I assigned to it). I count rows in my datatable before I fill it and it's 0, so why is my NewRow affected by Fill command? (I am using VB.NET 2005 Framework 2.0)
Is it possible to get the row index of a DataTable so that you can access the previous and next row? For example I have a DataTable that contains two columns ChapterTitle and PageURL. This is for a table of contents of a book. ChapterTitle is the chapter name and PageURL is an HTML page that contains the chapter (chaptername.html). When going into one chapter of the book I want to be able to tell which is the next and previous chapter.
After finding the chapter that I'm currently in how can get the next and previous rows?
I have been very stumped by this one. I have a fairly large (~1500 x ~1000) DataTable of positive and negative integers only that I acquired from a .csv file. For my program, I need to find the maximum value of the entire table, not just in a single row or column. Optimally, the code would be short and sweet, but that's not always the case ;).
The name of my DataTable is BeamMap and I am trying to return a value of MaxValue (already declared as an integer). I can post the code I have for creating the DataTable upon request.
Extra Credit: (not really)
Is there a way to quickly find the location (ie., row,column) of said maximum value? So far, all of the examples I've seen check cell by cell for a predetermined value, which is rather inefficient for the number of data points that I have.
I want to compare each row in Table1 with Table2 and also all the columns in each row.I want to do the following1. Get Row1 from Table1. Check if the same row is present in Table22.f Row1 is present ,Check every column in Row1 with corresponding columns of that Row in Table23. Bind Table1 to a Grid. Highlight the changed cells in Red.
Dim datatable_default_view As DataTable = DataTable.DefaultView.ToTable Dim servicenumber As String = datatable_default_view.Rows.Item(e.RowIndex)("Service Number").ToString If datatable.PrimaryKey.Length = 0 Then Dim keys(0) As DataColumn keys(0) = datatable.Columns("Service Number") datatable.PrimaryKey = keys End If Dim datarow_edited As DataRow = datatable.Rows.Find(servicenumber)
I'm trying to copy one row from DataTable to another, I looked almost everywhere and I can't find a reason why this is happening, I'm using ImportRow and still the New DataTable is empty. Here's one of the answers similar I found and It's still not working!:
Dim newTable As New DataTable Dim dsFrom As New DataTable For Each DBShoes In list Dim iShoeID As Integer
I have an asp.net application where I have a datatable ("DataTableA") that returns just one column ("ProductID").
I want to read each row of "ProductID", process some business logic, then copy both those columns (ProductID & ProductIDBusinessLogicValue) to DataTableB. This DataTableB is then displayed on the asp.net page.
What would bhe the best way to read each row of DataTableA ?
I am updating a data table (dt_report_crypt) from an encrypted csv file in the code below:I decrypt the colums and update the same dreport_crypt, such that it will contain de-crypted data.This part is working wellI however need to use this de-crypted datatable as a data source to update a second table(dt_report), using the sql SELECT command to filter relevant data,
Dim dt_report As DataTable Dim dt_report_crypt As DataTable Using cn As
I have the String and integers to which some values are assigned. now i need to read the string and integer values and assigned them to the datatable which i have created using VB.Net.
I have an application in which I have two text boxes in which I enter name and age, after I enter the name and age then I click the Add button when I click the add button then the Name and the age should be displayed on the Datagrid contol in the same application. But the data should not get saved in the Database, it should just show the data on the Datagrid contol. And they have told me that its mandatory that I have to use the DataTable object.
And when i click the Commit Changes then only the data should get saved to the Data base...This i can do .
Dim dt As DataTable = New DataTable("Intervenant") For Each column As DataControlField In grdvIntervenants.Columns dt.Columns.Add(New DataColumn(column.HeaderText)) Next
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I am developing in ASP.NET using VB.NET as background code. I am on vs2008 with windows 7 enterprise edition.I have just restarted doing VB.Net and my first time using a gridview without a DataBase, so maybe I am missing something. Basically, I am trying to add a DataRow (dr) to a DataTable (dt) and then put said DataTable into a Gridview (grdvIntervenants).My first step is to take the gridview and put all its data into a DataTable. Then i create a DataRow(dr) that I populate with variables and I add said DataRow to the DataTable. After that, I put the DataTable as the DataSource and bind the GridView.
The problem is that my GridView shows the rows but they are empty.While debugging, I found out that this error was beside all the DataRow.Item:"In order to evaluate an indexed property, the property must be qualified and the arguments must be explicitly supplied by the user" Seraching for it on the net.I did not totally understand the error, so i tried many different ways of adding the data into the DataRow but to no avail. I also tried different way of adding the column thinking the index problem might be coming from there, but again, the problem persisted. Now, something I found weird was that the Item property of my DataRow gives the quoted error, but I see the values into the ItemArray of the DataRow.I also found out that the same error appears beside the columns property into the dataTable.When I try to access the data from the DataSource in my rowDatabound method using the DataBinder, it gives me null results...
Im working on an Asp.net / VB.net website and coming from a C# / WPF background things are still a little new to me. I have declared a DataTable like so: Public notificationList As DataTable And I have then used the Page_Load event handler to populate it and bind it to a control on my page, which all works fine
[Code]....
However in another method i need to be able to access this DataTable, yet whenever I do it always appears as nothing. Do I need to be storing this value elsewhere like in the session etc?