I get "An unhandled exception of type "system.nullreferenceException. Object reference did not set to an instance of an object" while trying to save back to the database - relating to : da.Update(ds) , the last line of code in this listing. Trying to learn ... Imports System Imports Sys...more >>

Can someone explain to me why the following segment of code will not remove all rows from the datatable? My application is a Winforms front end connecting to an Access mdb back end. Public Sub ClearTable(ByVal pstrTableName As String) prpGetDataSet.Tables(pstrTableName).Clear() ...more >>

Is it possible to read the actual query structure from a SQL query on a SQL Server in VB.net? Also I want to be able to write a query into the server. I can't seem to find any articles on this, so if anyone out there has been able to do this, any help would be greatly appreciated. ...more >>

One of the requirements for our application is that on certain tables (so far about 2 dozen out of 300 right now) we need to track record changes. Meaning, we need a "history" of the table. We need to track who changed what record and when. The way I have thought about doing this is by crea...more >>

I have a query that is based on two other queries that are based on tables in a database. All of the queries that are used for this final query use grouping and totals. In the application I am making, I need to choose a date range to select the subset of the data I need. This is done in th...more >>

I have a table in my SQL Server that I am loading into a datatable. I am then saving the dataset that this table is a member of (it's the only table in the dataset) to an XML file so that I can use it offline in another part of my program. The code I use for this is: ds.WriteXML("c:\cli...more >>

I have a column named "PictureImage" in a SQL database defined as datatype=image. It has a Bitmap picture in it. (I verified the type by creating an Access project and a looking at the data, which access reports as "Bitmap Image".) In my VB.NET app I use the following code: Dim bytBLOBData(...more >>

I have to create a simple two tables mdb database for a vb.net applicaton. Is there in VS.NET a visual application (like VB5/6's Visual Data Manager) that allow to create/manage simple mdb database? Thank you for replying. Gio...more >>

Hi, Do u know where I can find a good simple example on how to use the enterprise library (data access application block) for windows application (not web). Thanks ...more >>

I'm using Visual Basic.NET 2003 and SQL Server 2000. I'm attempting to pass parameters to a stored procedure which will insert a record in a table. The connection to SQL Server seems fine, but when my VB.Net app reaches the ExecuteNonQuery() line I get an error:- "An unhandled exception o...more >>

I have just tried to run a simple application on a Win2000 PC and get the error message that I need MDAC version 2.6 whereas I only have version 2.53 How do I update to version 2.6 Thanks, Fred ...more >>

LOOP Try DaReports.SelectCommand.CommandText = "SELECT DISTINCT TimeSheets.Employee..... FROM (Employee INNER JOIN TimeSheets ON Employee.Employee = TimeSheets.Employee) WHERE ........ TimeSheets.Employee = " & Employee(x) DsReports1.Clear() DaReports.Fill(DsReports1) Catc...more >>

How can I get the Id (in a autonumber field) for the last added record in access? TIA! ...more >>

Sorry if this is too basic but I've been banging my head on this for = some time now. I'm using Visual Stucio 2003, VB.NET. I'm able to build a win form with = an OleDBConnection, DataAdapter and DataSet against an Access 2003 = database using Jet 4.0. I'm able to browse, move forward, backw...more >>

Hi, Do u guys know where i can fiund a simple walkthrough on how to use the = "Enterprise Library - Data Access Application Block" in a simple = application. Thanks...more >>

Hi, i was wondering if there is a way to have a class that would open a database connection, initialize a dataset based on a schema already included in the project and fill it. for this i should create dataadapters at the class level. My problem is that i only know how to do that on one form lev...more >>

I've added a new table to an access database programmaticaly, but when I attempt to add a new row, the code executes ok, but the new row is not added I saw the post about impementing the oledbcommandbuilder but I must be doing somthing wrong: Dim nrecs As Integer Dim AccessConnection As New...more >>

I've written the following code (which works) to retrieve a single value from an oledb dataset. Is there a simpler way to get a single value rather than iterate through the rows collection? (only a single row is returned each time) Dim nrecs As Integer Dim AccessConnection A...more >>

Hi all, I'm trying to connect to an SQL database from my vb.net form, but getting an error message. The code I used is the following: Private Sub ConnectSQL_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles ConnectSQL.Click Dim myConnection As SqlClient.SqlConne...more >>

Dear All, I am seeking a valid suggestions from your side regarding the sql server performance. my connection object get initialized at the time of login. I remain connected throu out the session that is I do not close the connection object on whole programmed on run time. what are your sugge...more >>

Can you direct me to someone who (for a fee) would show me how to connect from VB.NET to FoxPro free tables (.DBF files). I can pay via PayPal or other . I probably have a few other questions, but I would pay for help. Please email me at michael@erlewine.net Thanks, Michael Erle...more >>

I hope someone can point me in the right direction. I need to create an Excel file from a dataset. Any help would be hot Thanks David ...more >>

I have a problem using VB which I try to explain: In sheet A I have a table with : column 1: dates (e.g. 01-01-2005) over a range of 3 years column till 8: numbers In sheet B I have a row with dates (say row 1) what I want to do is to use the date of row 1 in sheet B, look it up in the t...more >>