Referencing A Column From Another Column In Datatable?
Feb 5, 2012
I have a data table, i want to add a new column on that table, the data in that new column will depend in the data from another column. Now i can think of two ways to accomplish this, first is loop through the whole table and do the statements to get my new columns appropriate data. the second approach would be to give the new column an expression, then convert the table to xml (to remove the expression) then convert the xml string back to datatable.
Now, is there any other way around this? what could be the most optimized way in solving this task?
I 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
After Filling a DataTable in GridView's DataSource . A column with check box Type appears but it created as read only column and I can't enable it or make it editable... even i tried .readonly = false and still can't be edited
I cant grasp it right now, lol. So here's what Im trying to do: I have two tables, a main table, and an employee table, with a foreign key in the main table pointing to the employee number in the employee table. Im trying to use a databound datagrid to show everything from the main table, and the corresponding name of the employee number referenced in the main table. Is there a way I can do that using DataSet.Table.Column.Expression, or what would be a simple way of doing this? I cant use TableAdapter b/c sometimes the database is offline, so preferably with datasets.
I have a sql stored procedure that returns a certain group of columns in my datatable. How can I move (let's say) the column in the first position, to the last position before I export the datatable to excel ?
Dim myConn As New SqlConnection(strConnection) Dim myCmd As New SqlCommand(strSQL, myConn) Dim dt As DataTable = New DataTable() Dim da As SqlDataAdapter = New SqlDataAdapter(strSQL, myConn)
I have a csv file that comes in I put it into a dataset and do a little manuipulation of the appearance of how the data is presented and then I put it back out into a different csv file that our 3rd party application will except. I was importing it into SQL Server and then doing a select statement to grab the data back out in the format I required. However I'd really like to eliminate the need for the SQL Server use.
So my question is how do I add in the 1st column of a CSV file the column name "KC" with a value of "1" there will only be 1 rows worth of data, mind you it's 55 columns long but there is nothing I can do about that, it's the way it has to be.So do I do this in the DataTable or when I create the CSV file? And how do I do this?
I need to limit the amount of columns being returned from a datatable from 14 to 5 or 6. Date, Hour and 3 to 4 decimal columns. Is it possible to do something like a SQL 'Like' to specify which columns I want?
So i create a datatable from a table i can't directly view(i.e. using sql server management). I want to find the column names that are in the datatable, what would be the correct way do this?
Dim s = (From rowItem In i.AsEnumerable() _ Select rowItem("COUNTER")).Sum()
I'm trying to Sum all the value in column 'Counter' in my Datatable. 'Overload resolution failed because no accessible 'SUM' accepts this number of arguments.
My problem is that i want to use the Compute method for a datatable.[code]The name of the column of that i want to sumarize is 2012, but it seems that the compute method doesn't recognize it as a column and throw this exception Syntax error in aggregate argument: Expecting a single column with a qualifier 'Child'.It is not possible to me to change the name of the column, what can i do in this case to sumarize the datatable and save it in a variable
I have following codes str2 = "select sno,name from employees where sno =" & Val(Me.TextBox1.Text) cmd2 = New SqlClient.SqlCommand(str2, con) da2 = New SqlClient.SqlDataAdapter(cmd2) dt2 = New DataTable da2.Fill(dt2) Now dt2 has two columns as sno and name But I want to add a 3rd column city type char(80)
I am trying to add data to a access datatable column I am using a richttextbox to fill in any data but when i save it to a column in a database and if there are more chars then 255 then i get an error (try to enter more then column lenght) anything under 255 is working fine the column in access = type of 'MEMO' so no limited to 255 it's the hystory to send that is giving me the problem
Dim history_to_send As String Dim day_to_send As Date Dim ID_to_send As Integer
I am try to filter some data and add to another datatable. While Run time the Error is shows Column *** already belongs to another dataTable Here My code:
I'm using VB.NET, but comments with apostrophes in here don't seem to be identified.And I get the exceptions for each case:
Column '[Cnpj Cpf]' does not belong to table Table. (fail) Column 'Cnpj Cpf' does not belong to table Table. (fail) Column ''Cnpj Cpf'' does not belong to table Table. (fail)
What should I do in order to ger a value from a field in a dataTable when the column name has spaces ?
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.
I use ADO.Net to call a stored procedure that retrieves data from our database.I put that data into a data table using this code below:' set Ready ResultIDs in databaseDim dt As New DataTabledt.Load(cmd.ExecuteReader)
I am having some trouble with creating a simple function that converts a column of a datatable to an array (containing all numbers). Upon running it, it says "Index was outside the bounds of the array"; however, I couldn't understand why my function would create this problem.Also since I do not usually program using VB.Net, I am not sure if my function has other errors (like syntax errors).
I am getting a syntax error " Missing operand after 'Price' operator" with the following code, which should be right but obviously isn't. Any thoughts on where the error is?
I have a datagridview which is populated from a datatable. This works fine. But if i run it more then once i get a column name "example" already belongs to this datatable. Ive tried everything to clear all the columns of the datatable and the gridview but still the same
