Ive created a form to add/delete/update records in a database ,but when i try and open the frm i get a NullReferenceExceptionUnhandled error, below is my code, i cannot for the life of me see where i've gone wrong, but maybe someone else can spot it?[code]
I have problems with the updating and deleting of records in database. I'm using ObjectDataSource and the GridView to display the results in the database. Below is the codes for the update and delete (in the DAL (data access layer). BTW, I'm doing 3 tier architecture in VB.
'update the records accordingly in the database. Public Function UpdateBooks(ByVal title As String, ByVal borrowDate As String, ByVal dueDate As String, ByVal NameBorrower As String, ByVal book_id As Integer) As Integer Dim connectionString As String = My.Settings.dbConnection [Code] .....
I don't know why, but every time I try to update (by clicking on the update button), every thing is not updated, the page would refresh then the records still remain the same in the GridView. As for delete, when I clicked on the 'delete' button, the record is not deleted, it still remains there.
These are the codes in the (BLL (business logic layer)): Public Function getUpdateBooks(ByVal title As String, ByVal borrowDate As String, ByVal dueDate As String, ByVal NameBorrower As String, ByVal book_id As Integer) As Integer Dim ds As Integer = UserDA.UpdateBooks(title, borrowDate, dueDate, NameBorrower, book_id) Return ds [Code] .....
I display my records using datagridview...I have also Save button which is intended to update any changes I make via the datagridview.I got this error whenever I type something in the address column "Update requires a valid UpdateCommand when passed DataRow collection with modified rows."[code]What code do I put so that whenever I highlight a row and click delete button or press delete key selected records will be deleted from datagridview as well as my database will be updated from any deletion?
How do I insert,update,and delete records in vb.net 2008 from a Access 2007 database?Really, I figured out how to add records - but I cannot delete or update records. Any pointers, website tutorials, etc?Also, I am binding the database table to Listbox which is working, but I need to update the listbox with deletion and update changes too...
I have used this form to add new records on my database(ms access) in my database I have a column name 'ID' which is my primary key 'ID' is set as auto number. Now I am having a trouble on creating my update and delete button it's always saying "cannot be delete/update"
Here's my code on add, update and delete Public Sub SaveRecord() Try Dim dbConn As OleDbConnection Dim dbInsert As New OleDbCommand Dim str1, str2, str3, str4, str5, str6, str7, str8, str9 As String [Code] .....
Note my add is working perfectly fine. I just can find the error on my delete and update. Also I have used this to view it to my datagrid I don't know if its the right thing but it's working fine too. 'declared dbpath globally' Dim dbPath As String = "Provider=Microsoft.Jet.Oledb.4.0; Data Source=../VG.mdb;Persist Security Info=False" [Code] .....
Another thing is how to code each textbox and combobox to bind it to my records so that when I click on the datagridview each column will be distributed on each respective textbox.
i have a simple application which can create/update/delete/search records using Access database. If i add a record, save it, then close the application and run it again and search for that record, it appears. However, when i write some code to my application, nothing to do with the search function, and i run the application the record is not found. For example i added a button to clear the textfields, and when i ran the application the records i have added earlier were not found.
A VB.net program reads the queue and calls a stored proc in SQL Server that processes and then inserts the message into another SQL Server table and then deletes the record from the oracle table.
We use a DataReader to read the records from Oracle and then call the stored proc for each of the records. The program seems to be a little slow. The stored procedure itself isn't slow. The SP by itself when called in a loop can process about 2000 records in 20 seconds. But when called from the .Net program, the execution time is about 5 records per second.I have seen that most of the time consumed is in calling the stored procedure and waiting for it to return.[code]...
I have a datatable populated from an SQL Server 2008 database table. I created a DataAdapter with a commandbuilder to manage the updating, inserting, and deleting of records. The Updating and Inserting work as expected. However, Delete does not. The code runs through just fine without any errors. The number of records in the datatable after the row is deleted even reflects the deletion. The DataAdapter.Update works fine without any exceptions. But when checking the actual table in the SQL DB the deleted record is still there.Here are the parts of my code that deal with this table.
I'm creating a project using Microsoft Access 2007 & Visual Basic 2008.I have two tables in my database, Staff and Training Attended. The Training Attended records of Staff are displayed in datagridview, residing in a different form from the Staff detailsWhat my program does is, it will display all of the Staff's list of Training Attended in datagridview once I click the button in Staff form. I've succeeded in retrieving the records. using bindingsource.filterThe problem is that I can't insert/update/delete records in the Training Attended datagridview. it keep giving me this error: Update requires a valid UpdateCommand when passed DataRow collection with modified rows.
I'm creating an application that adds and deletes records from a microsoft access database. The language I'm using is VB2008. I am importing the database through a wizard. I can add records and delete records, but I cannot delete a newly added record without closing the form first. When i reopen the form, I can delete the record. Here is how I have my database setup:
'Bind user info to the controls. AUSERDataSet = New BulldogUsersDataSet AUSERTableAdapter = New BulldogUsersDataSetTableAdapters.UsersTableAdapter AUSERTableAdapter.Fill(AUSERDataSet.Users) ' Setup the binding source. AUSERBindingSource = New BindingSource
how to do it, but the tutorial is not applicable on the program that I wish to do. The tutorial tells you to add 4 navigation buttons so that you can navigate the database(first, last, back, and forward). Then an update and delete button. But if this is what I will do, it would take 10 years to navigate the database and update a record. Now, what I want to do is just for the user to input a unique ID and click search button(which I have already done). Then the update would be easier. How can I update or delete a record using this method?
I have a project that I am working on that requires me to delete records from the database if they are atleast 3 years old.I have something like this in DB2 SQL to get the date:
SELECT * FROM tableA WHERE ADD_DATE < CHAR(CURRENT DATE-3 YEARS)
ADD_DATE is stored as Characters in my system, this is why I am converting I know it is also possible to get the date and format it in VB.net which is the language I am using to call the SQL statements.My question is whether it would be faster/better to get the date and perform the conversion inside the SELECT in SQL or would it be better to get the current date and convert it in VB.net and then use that date in the SQL statement. I'm thinking VB.net would be better because there are thousands of records that must be compared. I should be able to set it up in VB so that it only retrieves the date and converts it once but I am not sure what kind of performance hit each takes from these statements.
I am trying to Insert/Delete records in a MSSQL database based on if a checkbox is checked or unchecked. The checkbox is an item template in a datagrid, I can check/uncheck the checkbox but it doesn't do an insert or delete. Here is my code:
But then I get the error that the control chkmap has not been declared. I am confused as to how this needs to be declared, do I set a variable to the FindControl("chkmap") and then set it as variable.checked = true ?
I am using Visual Studio 2008 for creating a Winforms app. I have connected a database to it called XStats. There is one table in it called XGames and in that table 2 fields, XIndex (the primary key field) and GameNumber. Using the following code I can add records to the database, the data is taken from a text box, but once added I cannot view them unless I shut down the app and restart it.
con.ConnectionString = connectionString con.Open() Dim cmd As New SqlCommand
The existing records in the database are displayed on the form in detailed view via a binding navigator. How can I make it so that I can view all the records in the database, even those that are added during the current session. As will be obvious, this is my first attempt at creating and using a database with a win forms app,
how to update records on an existing access database using vb.net with just a textbox and a command button and how a specific record of a field can show up in a label or a textbox
i connected vb.net to my access database by just clicking on "add new data source">>"new connection">>"microsoft access database file" and just continue..tested connection and done.
you can see in the screenshot of my form, by default the left side textboxes are disabled but they're enabled if the user checks the checkboxes and disabled again if unchecked.
assuming that the textbox is already enabled and i want to enter a value in the Brewed Coffee area of the form...for example 5. when i click on my Submit button the value of that particular record in the database will be updated, so in my table the value of the quantity field in Brewed Coffee will be 5.
another thing is that how can i see a particular value on a label or textbox from my database like on the Prices area. in my database if a product's price is 80 then it should show a 80 in the label. the values of the prices from the screesnshot of the form are not the ones on the database xD i just typed them in.