VS 2010 Break Down A DataTable Into Groups Of Rows Ones With Same Traits Under Column?
May 3, 2012
I have a Datatable with one column of the table being 'PartNum(product part number)'. I used EntriesTable.DefaultView.Sort = "PartNum ASC" to sort the whole Table, with respect to the information in this column. Now I'm just trying to further sort the table by grouping rows that have same info under that column together and do something to each of such groups. but I'm kinda stuck here.
I'm thinking of creating some sub-DataTables out of the original one and have these sub-tables to hold those rows with same info under "PartNum". Does anyone have ideas how to do that? maybe with DataReader or DataView ,
I have three sub tables that I want to process. For each I want to combine the rows, as they are only different by contents in the second column(I want to do the same to the fourth column, later):
I have a Data Table Column with multiple Rows of data. I need to search all lines of TextBox1.Text for any data that is identical to any row in the specified data column ("MCaddRG"). Also any identical findings need to be made into a new text file or a new form with a text box.[code]...
*Also if it is possible I would really like to have a check box list that contains the data from the "Device" columns so I could check the "Device" and then it search the TextBox.Text for the checked "Device's" "MCaddRG"
i 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?
I'm trying to query a DataTable to get a collection of rows but I'm finding that my search string has to be the exact length of the columns width. So, for example this won't work:
Dim rows As DataRow() = (From r In myTable.AsEnumerable() Where r.Field(Of String)("fname") = "Bob").ToArray()
...but this will:
Dim rows As DataRow() = (From r In myTable.AsEnumerable() Where r.Field(Of String)("fname") = "Bob ").ToArray()
The search term ("Bob") has to be padded with spaces to make it equal in length to the column width (10 characters). Is this how it's supposed to work or am I doing something wrong?Also, how can I do a LIKE search? So for example, I want to search for all names that start with "Bo" or whatever. ie. "Bo*".
Using con As New MySqlConnection(strCon) 'get users direct friends Dim cmd As MySqlCommand = New MySqlCommand("SELECT distinct f.* FROM friends f WHERE (f.UserID = ?UserID) AND (f.FriendUserID <> ?FriendUserID)", con) cmd.Parameters.AddWithValue("?UserID", UserID)
[Code]...
now I need to create another command, datatable and datareader in this same function and add the rows of that datatable to the one above. What is the most efficient way of doing this?
I want to delete the rows of a DATABLE that verify a criterion. Someone would be so kind to show me how do this.For example, I have a DataTable with "customers" and I want to delete customers who live in "Madrid"... criterion: CityCustomer='Madri
When I query a DataTable using LINQ, are the rows returned as references? Either way, is it possible to control this behaviour, so that rows are either returned as references or as new rows?My guess is that all objects are returned as references by default, since that seems to be the normal behaviour in most programming languages.
I'm trying to load a datable into a datagridview, but column1 ("date") should be converted to a datetime, so I can sort it when I click on the datagridview header. I tried this, but it gives me that there is no column 0 or one. I have 2 columns: "ID" and "DateStart"
I have an application that users will save a list of clients to a database. The extension on the database is .sdk, and I think is some kind of sql database. The user can save rows and add rows to maintain a client list, but when I release an update, I have to install it without the database file. If I install with the database file, then their current client database is replaced with a new blank database.
my issue is that I need to add columns to tables in their existing database without overwriting their current rows. For example, i have columns for client name, address, and phone number currently. On my next update, I want the user to be able to save client birthdays. Here is what I have:
I have text files with X Y Z data. There are three columns, one each for X, Y and Z and the files are tab delimited.The value of X is constant over a (repeating) range of Y. Z is the dependent variable.
For example:
0 1 44 0 2 32 0 3 22
[code]....
I need something to take this file and break into multiple tab-delimited columns. In the output, I would like the initial range of Y to be the first column (ie 1 to 4). Then, the second column should have the Z values for that domain (X=0 in above example). Then, the next column should have the Z values for the next domain of Y (i.e. 1 to 4 again, but now for X=5 in above example) and so on. Also, I'd like the first line value in each of the new columns containing Z values to be the X-value they were originally associated with.Thus, I'd like the output file to look like
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
Dim _tableBackLogs As System.Data.DataTable Do While i - 2 > 0 _tableBackLogs = Global.DataAccess.GetDataTable("SELECT SubjectID,SubjectName,Grade FROM SubjectPI WHERE RegNo='" & CInt(HttpContext.Current.Session("userName")) & "' AND Status='Fail' AND Semester='" & i - 2 & "'") i = i - 2
Doing this replaces the previous data in the DataTable. I want to retain the previous data i.e i want the new rows to be added to the DataTable w/o replacing the previous rows.
In my grid I have data in two columns same for couple of rows. Then again couple of other rows will same with different data.I want make them into alternative sections with colors In below example(image).
Rows no 1 to 4 has 'High', 'High'. I want make them gray bgcolor for those rows. Rows no 5 to 8 has 'High','Low'. I want make them white bgcolor for those rows Rows no 9 to 12 has 'High','Medium'. I want make them again gray bg color for those rows.
i have a datagridview with three columns. i set the first column to visible=false, so the user can only see two columns.when the user presses the tab key in the first visible column -- column(1), i want to ignore column(2) so that the user only tabs through the rows in column(1)i can't get it to work. it will always tabs through the rows in column(2) even if i use the column name.
I have a datagridview, and I want to get an array of rows, or rows indexes in which boolean column "Aktywny" is set to True.Obviously I can Do it using loop, but LINQ will be much faster for sure...
I have a DataSet that contains 1 DataTable, and the DataTable contains only 1 row of data. I want to loop through all columns in that row and say:
Column name = column value
so for example if the column name is FAVORITE_FOOD and the value is pizza, I should display FAVORITE_FOOD = pizza I can get the column name from column.ColumnName and the value from Rows(0).Item(0), but for the life of me I can't put it all together in a simple loop.
Could someone enlighten me on how radio buttons work?Is there a way to retrieve a single value from a group of radio buttons that indicates which radio button in the group is checked?
In the documentation, it said to set the "Group" property; however, my radio buttons don't have a group property, at least that I can find.
I realize that I could iterate through the radio buttons and find the one that is checked, but that seems like it defeats the purpose of radio buttons.
So I have some vb.net code, and I have a nested For loop inside a For loop, and then I have EXIT FOR statement, will it break out of one loop, or the whole chain?
I have a form with a textbox and a add button. User can write a name down on the textbox and click add button. it will save in a datatable with auto ID. After that, the textbox is cleared and the user can write another name on the text box and click the button. This should add to the existing datatable on memory with existing ID + 1. Show on the gridview. (this is just for display purpose to confirm it works)
I have a datatable like this. Button1.click() event Dim name = txtname.Text Dim dt As New DataTable dt.Columns.Add("ID", GetType(Integer)) [Code] .....
At the moment I have sometime like the code above. in the real program, it is not just name and it is not just one datatable so i just mock up some code. And this code for aspx. <asp:TextBox ID="txtname" runat="server"> </asp:TextBox><asp:Button ID="Button1" runat="server" Text="Button" /> <asp:GridView ID="GridView1" runat="server"> </asp:GridView>
I load data from a table and I want to sort it into groups by month. My problem is this, if the header does not exist, it will create one and add the item into the group, but any further headers with the same month get added to the 'default' group and not to the already created group. Here is the code I using.
I Have a datatable in .net. I need to flip the location of two of them. For example, a datatable that the select statement had an order by priority clause. The user wants to up the priority of a single row by selecting it and clicking increase priority, how do i move a row up (AKA flip two rows)
Private Sub error_out(ByVal line As Integer, ByVal err_col As Integer, ByVal err_msg As String) Dim ln = t_erori.Rows.Add
[Code]....
I suspect this is because it's trying to add the same row twice. How can i make this work ? Or what else method could I use to do this ?
I need this datatable because my app is writing some results in there, but any other method to store the results that works with parallel.for would be ok.
The problem is I want merge duplicate serial_no into one row which the value of testong adding to new column. I have tried many ways, but I can't find the solution. Here is my code behind :
