I'm creating a program which navigates through a tree-like structure. There are lots of items with a single 'parent' and many 'children'.
Using a SQL database, I've got all of the items information stored, but I'm struggling with how to hold the IDs for each Items children.
For example:
A: no parents, Children: B, C, D
B: Parent: A, Children E, F, G, H
F: Parent: B, Children: J, K, L, M
Where each item will have hundreds of children, for which I don't really want a column for each child...
Is there a simple (or more complicated) way to hold and retrieve a large number of integers within one column... i.e. as some kind of sub-database, or an array with the column??
I am using the following code to alter an table imported from an Excel spreadsheet
Dim SQL As String = "ALTER TABLE receipts ADD payee integer, account integer, category integer, reconciled boolean" Dim dataread As New OleDb.OleDbCommand() dataread.Connection = Connection1
[code]....
Both ExecuteNonQuery() actions yields the exception message {"Syntax error in field definition."}The error message does not happen with the first if the boolean column is not there (I tried Tes/No as a definition - but that also failed.The second query to modify the ID column from autonumber to integer I assume fails because it is a Primary KeyHas?
I have a datagridview.. It is unbound to any database and has 2 columns..1 is item name and other is amount/expense, incurred..I want the total of expense incurred be displayed in the textbox on button click ie adding the numbers in amount column..
I'm having an issue with using code to update a program that's trying to save data to a database. The problem is where I have found many answers on restricting the number of rows updated. All data that I have is on a single row in the database. Here's the code that's absolu
I have a database of more than a 100 columns, what I would like to do is to be able when I do my search query, is to be able to choose using checkboxes which data I want to appear in my result table. For example, I have master datas (name, adresses, registration, ...) and financial datas (returns, ranking, ...) and I would like to be able to have either one of these two datasets or both of them in my result table. I'm assuming that I need to use "IF" sentences (if checkbox1 is true then...) but I have been struggling integrating my sql queries in VBA. how to implement this minor thing?
i have an ACCESS database with 3 columns. I establish the connection with the VB 2008 Express and put the data in the form but i don't know how to add the text of a textbox in the database.
how do i get info from 2 different columns in an Access database and put them together in a drop down menu. (i know how to get data so that i can see it in just a textbox but i dont know how to put 2 data together and then display in a drop down.
another question is how do i save info that has been changed back into the access database i got it from
last question- how do i make a textbox only take numbers
I created a database in my project, and added a table and some columns to it. Now after making several changes to the program I decided to add some more columns, but for some reason those new columns don't show up in the SQL query builder or the database explorer. I realize that this is an oversimplified explanation
I have a re sizable panel which i am adding over 100 buttons to. to do it i have a timer which detects any change in the height or width. then clears the panel and re draws all 100 buttons on. however i am encountering issues with flashing (where the buttons are gone for a split second before being repainted) and also speed issues. it seems to be slowing down the users ability to re size the window.
i was thinking by adding the buttons through its own thread it might combat the main (speed) issue.
The data is loaded from a xml file (which the code parse the xml, and create datagridview cell dynamically). and the user is allowed to change the data, when the program exists, it will write back to the xml file to save the change.It works fine when there are not many rows. when it has too many rows, say, 10K rows, the program loads slowly. I searched, found some suggestions, but it seems they do not work very well.1) when load the data, not create the rows directly. instead, create a datatable, then add the table to the datagridview's data source. it still takes time for the dgv to show the data.
2) then, I guess maybe I should paging the dgv. then it comes 2 questions:2.a) I only have a manually created table, how can I get a dataadapter/dataset from it? do I have to put data in a database table first (i.e. sql express), then load it to data adapter? is it possible to manually create a data adapter/dataset?2.b) if I paging the dgv, does it mean I still need manually update the dataset/datatable to keep the possible change when the user navigate through the dgv? or, I can simply use an update method?
I have a lots of strings.So I will need to do some statistics.The problem is some strings are the same.So,I will need to know the numbers of the same strings.How to do this.Shold I hold the strings in a Array of a List?
I want to show lots of text in my form but i'm not sure how to do this efficiently.
The text is just instructions to the games Pong and Match so it isn't very long, but long enough to not be practical to type into a textbox's text control. The instructions will have paragraphs, but no other formatting.
I have a form with lots of labels on it, and a reset button to reset them to a default text. This reset sub has lots of lines of code to get this done, but I think it cen be done in just a few. I thought of something like:
For Each Label In Me.Controls Text = "0" Next
but this doesn't work, or anything else that I've tried. how to do get this done? And what if I want half of the labels set to 0 and the other half to 1? Would that be possible without setting them all seperately?
I'm considering making an application that will perform various tests against servers on a local network - for example pinging them, checking hard drive space, checking the state of services, whether or not databases are available, etc etc. Very similar to Hostmonitor if anyone has ever used that - but my app will be free
These tests would have to be performed at specified intervals, but the problem is that there could be literally hundreds of tests and I'm not sure how well my app would cope with hundreds of timers running... especially if they are all configured to run every minute or two (they all need to run independently of each other).
Really I'm just wondering how you guys would design such a system.The best way I can think of is to have a separate timer associated with every test and then when a test's timer has elapsed use the ThreadPool to do the work that the test will perform. That way if loads of them happen to run at the same time then the ThreadPool will queue them rather than trying to run say 200 at once. I also think I would need to have some kind of staging for when the app first starts, so that every single test is not going to have the exact same time to run (well, every test that has the same interval configured), but that shouldn't be too much of an issue.I guess it would be a good idea to try and use some sort of grouping so that more than one test can use the same timer - like if 20 tests were set to run with a 5 minute interval then I could use one timer and run all of the tests when that one timer fires.
I am going to work with 300 000+ words... what is the best thing nowadays to put so much text so it can be searched fast (runtime)? I would use a jagged array but maybe there is something new since I read my last book with tips&tricks.
-how do i type the code to minus out the number from "Leave_balance" (in the Staff table) with the number from "Days_apply" (in Leave_application table) eg: 10 days (from "Leave_balance" Staff_ID "S0001") - 2 days (from "Days_apply" ID "abc") = 8 days and then update the "Leave_balance" of staff_ID "S0001" with 8 days
I am in the process of writing a program that converts large number of records from one format to another. When doing some testing on it, to make sure I don't have any memory leaks, I am noticing a large number of undiposed cursor objects. I am not sure what to do with these. My program seems to run fine, however on some computers I am getting issues when the process is complete.
What happens is this. The program starts up, the user sets up the configuration options, it does it's processing, it creates a HTML report and launches IE (or whatever their default browser is) to display it. Then the program goes back to its Config display.
I have a DataGrid, with several columns. One of them is DataGridViewComboBoxColumn. I have a lot of items in this column - more than 1000 - and I need all of them. So grouping is not an option - all items must be there, users must be able to select from all.The problem is, DataGridViewComboBoxColumn becomes painfully slow, when number of items is about 1000, and above. This issues is well known to Microsoft, it dates back to Visual Studio 2005: [URL]...The problem is still present in Visual Studio 2010. Any ideas how to solve this?
Is it possible to fill DataGridViewComboBoxColumn with data partially? I mean (that was functionality fully working in Access), when you click DataGridViewComboBoxColumn, some items are displayed (lets say, 100 items). When you scroll down to the latest item, others are loaded (another 100) and so on. I don't see any other option to make DataGridViewComboBoxColumn working faster? Problem is, how to implement this? Has anyone meet that problem before?
how to go about changing the tooltip on 114 buttons. As you can see from the code below I need to change the tooltip information based on if there is data in an array of structures. I tried creating a string of the button name and passing it on but that did not work.
Private Sub Form1_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load Dim tooltipstring As String
I have a DataGrid, with several columns. One of them is DataGridViewComboBoxColumn. I have a lot of items in this column - more than 1000 - and I need all of them. So grouping is not an option - all items must be there, users must be able to select from all. The problem is, DataGridViewComboBoxColumn becomes painfully slow, when number of items is about 1000, and above. This issues is well known to Microsoft, it dates back to Visual Studio 2005:Is it possible to fill DataGridViewComboBoxColumn with data partially? I mean (that was functionality fully working in Access), when you click DataGridViewComboBoxColumn, some items are displayed (lets say, 100 items). When you scroll down to the latest
I have an App. I have a lots of datas to handle.So,I wonder if I can click a button and launch Excel and export my datas to Excel.So I can edit my datas in the Excel rather than in my App.
How would I go about copying all the files out of a directory and lots of subdirectories and moving only the files somewhere else?(say C:Testfile1.txt).
I am reading a record from a database into a datagridview.I have changed the column "ComputerAwareness" from a textbox column to a combobox column.This column is at the 21st position in the database but after changing it to a combobox in datagridview it is diplayed as the first column in the datagridview.How can I keep the position of this column same as in the database?I have googled a lot for the solution and tried all the possible ways but none seem to work.One of the ways I tried is in the code below.
Private Sub DisplayButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles DisplayButton.Click Dim cs As String = "Provider=Microsoft.ACE.OLEDB.12.0 ;Data Source=C:\Users
I am currently using microsoft access 2007 and vb.net 2008. The problem senario is this: I have a database-table that contains two columns, items, and the price of each item. I tried to drag this table to the form as a checkbox tool, but only one checkbox1 was diplayed. The table consists of four rows. My requirement is when I drag the checkbox I want to see the all items in the first column, i.e. four checkboxes that hold the same name as in the table in the database, and when I check one or more items to be able to use, in somehow, the price(s) to make some kind of calculations.
Private Sub Table1BindingNavigatorSaveItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Table1BindingNavigatorSaveItem.Click Dim dg As DialogResult = MessageBox.Show("Would you like to continue saving your changes?", "Save Changes?", MessageBoxButtons.YesNo)
easy way to simply load the data from database into a datagridview with one of the columns being a comboboxcolumn. Apparently there is no selectedvalue, selectedindex or value as in a combobox to return the combobox value. What I need is to verify if the database value is 'true' and if it is then I need to set the comboboxcolumn with a specific value.
Ex:
if ds.tables(0).rows(0)("flag") = "true" then datagridcolumn.selectedvalue = 1 else datagridcolumn.selectedvalue = 0 end if
-how do i type the code to minus out the number from "Leave_balance" (in the Staff table) with the number from "Days_apply" (in Leave_application table)
