VS 2008 Updating Database - Producing Duplicate Values
Jul 29, 2009
Here is my
cn = New OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=BHgardeners11.mdb;")
cn.Open()
Try
str = "UPDATE Products SET ProductCode = ?, ProductManufacturerCode = ?, ProductsTitle = ?,
[Code] .....
If there is only one item in the database, then this code works. If there is more than one record then the error is produced that it is trying to produce duplicate values. This is down to the Primary key in my database which is the only thing that cannot have duplicate values. However, when I remove the primary key it has the predictable problem that it goes crazy and does weird things.
How can i avoid the duplicate values in the Access Database?? I am working in VB.NET, to create DataEntry Form. I have Combobox. When enter the value on Combobox and press OK button then the value should check on the database , if the value is not there then it should save on the db. else the Missage will give "It is Saved".
I want to insert number for City_Id and City_name , i wrote a query for auto generate number for City_Id,working fine but in the city name i want to avoid inserting duplicate value like if Mumbai is a City ihave already saved then system should not allow that name again. neither in small or in capital or mixed letter.
I am sending values from Combobox and Textbox to Access Database in VB.NET.I am phasing the problem when i enter the Duplicate values.In the database one of the column is Indexed.(Yes Duplicates not allow)That column i bind to Textbox("txtperson1").I used the TRY and Catche method to solve the Indexed Problem.when i run the application the value which i enter is not a duplicate that value save on the db. Once i enter the Duplicate value , the message box is showing "The Record alread saved".But After i enter the new value the same message is displaying, it is not saving on the db.
I need to create an array, then iterate through a string, adding the string value to the array only is it does not already exist, to produce an array of unique values. The issue I am having is with the array.length operation - on a array that is nothing I am unable to retrieve the array length (0), as such I am unable to redimensionalise the array to be array length (must be array length as arrays are indexed from 0), providing me the ability to add the new value to the array and then continue the loop until all values have been checked to see if they exist within the array (using contains) and the value contain only unique values..
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
if textbox1.text =S1, S2 then on button click event the S1 and S2 column value of Table in MSSql2005 database will be updated with the value "b" where date=1/3/2012
The problem I'm facing is that the update happens correctly only for the first of many values. All the other values are calculated and consequently, updated incorrectly in my table. I am almost certain that the looping is what is causing the problem but have been unable to find a way around it.
For some reason my code is executing the INSERT query twice and putting duplicate records in my table. If I put a primary key on one of the fields I get a runtime error and it complains about the fact it can't add the record twice.
The part of the code that INSERTs is near the bottom, bolded and italicized. I put the entire IF statement of code incase my logic is wrong.
This is what's being executed when a user clicks a button
If listOfCompanies.Contains(cbx_Company.Text) Then 'If the list contains the company, UPDATE the record If LaborChecked Then
(The following code cant work , it just wont update.. my bar default max is 80 and its still shooting over 80, its not dividing)
Sub displayprogress(ByVal amount As Integer, ByVal progress As ProgressBar) progress.Value = 0 For i As Integer = 1 To amount
[code]....
i did try replace the question with SQLLquestion(0) but the result given was 0 and not the question from database i tried calling function sqlquestion() from one of the form but it just cant work i think tis wrong...
I need to parse a log file from some information provided via an external command line application. The problem is that the command line app doesn't produce its on logs. So, I was wondering how I might be able to obtain the information form the command line. The only thing I could think of was to redirect the output to a TextBox, write it to a text file and then parse the data. Does anyone know of any other to do this?
I am trying to get information into a database from VB 2008. I have an established connection and have pulled fields onto my form. I am able to see data already in the database on the form. Originally, I tried to use an Update button to send the data from the dataset to the database. This did not work. I then added a Save button to the Navigator on my form in hopes this would do it. This too, failed.
Iv created a Stock Market program and i need it to automatically download the new prices from the web on a daily basis.
It will be downloading the info from my own website - what server software should i use to manage this - simple machines forum ?? A mysql db will be on the server - how is it best way to get this whole system working ?
Having problem in updating an existing record. An error occurs "Data Type Mismatch in Criteria Expression"
Private Sub ToolStripButton1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ToolStripButton1.Click Dim myBuilder As OleDb.OleDbCommandBuilder = New OleDb.OleDbCommandBuilder(dataAdapter)
I am trying to make changes to parts of an Access table but can not get the database values to change.I am able to get the datasets and things in VS to change, but the database never shows the changes.
I Have: ' Create an instance for the payrolltable Dim dt As New MsPeachDataSet.PayrollDataTable
i m having problem while updating my database... In this code when i delete records then it will deleted but it can't show updated data..for viewing new updated data i hav to again open the form ... so is there any code which i miss??? to update database @ runtime??
i'm just starting with sqlite, as apparently its quicker than access for a real time logger. i'm using this as a tutorial - i didn't install the runtime support with SQLite as it causes issues when using 2008 express.[URL]..
but it seems the data isn't being written to to the db. i can't tell exactly because i dont have a program to view the table contents, only to view the setup of the db.
I am working on a project that stores data on animals. I am trying to make updates to data already stored there, through inputs on a VB form. A form where all the data is populating the fields shows up and the user can change/update any field. Once they are finished, they click update and the DB is supposed to reflect those changes (Theoretically)However, I wrote the code to do that, but when it runs nothing in the database is changed and nothing gets done, as it seems. No errors appear and nothing goes wrong with the program. It just doesnt change the data in the db.
I am working on a project that stores data on animals. I am trying to make updates to data already stored there, through inputs on a VB form. A form where all the data is populating the fields shows up and the user can change/update any field. Once they are finished, they click update and the DB is supposed to reflect those changes (Theoretically)
However, I wrote the code to do that, but when it runs nothing in the database is changed and nothing gets done, as it seems. No errors appear and nothing goes wrong with the program. It just doesnt change the data in the db.
Here is the code updating the database.
If txtNewID.Text = "" Or cmbRegion.Text = "" Or txtWombatName.Text = "" Or cmbGender.Text = "" Or txtAge.Text = "" Or txtWeight.Text = "" Or txtLength.Text = "" Or txtCommunity.Text = "" Or txtDescription.Text = "" Then MsgBox("Please fill in all required fields.", , "ERROR") Else
I have two forms in my program, Form1 has ListBox which contains names from the Database.Form2, has textbox and add button to get a new name from the user.but when I click on add button.. i return to Form1 to view the names in the listbox by clicking on view button: ALL NAMES ARE DISPLAYED WITHOUT THE NEW NAME.when I close my program and click on View button all names including the new name that was entered before are displayed ! is there a way to display everything in the database without closing the program??I need a way to refresh or something.
Form1:
Imports System.Data.OleDb Public Class Form1 Dim ds As New DataSet()
I have spent several hours trying to delete a row and insert a row into an Access database using the OLEDBDataadapter and dataSets without any success. I don't get any errors it just doesn't update the datatable. Here is the last version of the code I have been trying to get to work. I have done a lot of searching and have
Data save Private Sub SaveNumDte(ByVal ltoNum As String, ByVal ltoDate As Date) Dim numTotal, x, MaxRows As Integer
I'm using an unbound data grid in Visual Basic. I made the following loop for the purpose of searching each cell and each column for a duplicate value. But for some reason I get a "InvalidCastException" when I try to add a second row.
Private Sub AddJudgeBtn_Click(sender As System.Object, e As System.EventArgs) Handles AddJudgeBtn.Click Dim exists As Boolean ' ToDo: If the value entered is already on the list, don't add again. If JudgeList.Rows.Count() > 0 Then
I have a datagrid view that displays information from a table. Changes I make to the data grid view are not saved. I have a button called btnsave but I have no idea what to put in the click event to save changes to the DB.
vb Dim ConnStr As String = String.Format("Provider=Microsoft.Jet.OLEDB.4.0;Data Source={0}", DataDir) Dim conn As New OleDb.OleDbConnection(ConnStr) Dim sql As New OleDb.OleDbCommand("Select * FROM USERS") Dim dt As New DataTable [Code] .....
I'm having trouble updating my access database using DataGridView1 on my form. I created a DataGridView on my form linking it to an access database data source. At run time, the DataGridView shows the content of my access database. When I edit the database data in DataGridView, it looks like the database is being updated but when I close the form and reopen, the database is not updated. Do I have to write code and assign it to a button to update the access database? Is there a way to update the database once a new value is entered in the DataGridView? Am I missing a setting that does this automatically?
I have a small program with Members table and for subscription. The table has a joindate, expirationdate, status and gracedate collumns. When I run my program n click on a button I want the program to update the STATUS text by checking expirationdate column if is greate or equals to todays date then Set it to Expire.[code]Here is the error message I get on runtime: Syntax error in string in query expression 'Expirationdate <= '26 July 2011'.All I need is to change the status text into Expire if expirationdate <= todays date.
Is it safe to update an SQL database from multiple threads at the same time? I have a method which runs on up to 25 thread pool threads at the same time and it attempts to write to a text file and update an SQL database - I assumed that writing to the file would not work properly if all threads tried to write to it at the same time, so I have used SyncLock for that part of the method. Just wondering if I need to do the same thing for the part of the method that updates the SQL database? or is the framework (or SQL server) smart enough to either execute multiple update statements on the same table at the same time without a problem or queue them?
