Here is how you can connect and build a Access data base application in Visual Basic.Net. First we need a connection string and Data Adapter or a command object for executing SQL statements. We can execute SQL commands using either the Adapter or the OLEDB command object.
In ADO.net there are plenty of class which make connecting database smooth as silk. Lets do it
Create connection string
Public Company As OleDb.OleDbConnection
Now we can configure the connection string.
Company = New OleDb.OleDbConnection
Company.ConnectionString = “Provider=Microsoft.ACE.OLEDB.12.0;Data Source=D:\.Net Project\Accounting Pack\AccountingPack.accdb”
We are ready to interact with any table in AccountingPack database
Interacting with table
As far as we got everything is right and need to add, retrieve,update and delete rows to the table in the data base. The CURD operation can be made possible with a command object.
Company.open()
Dim cmd As OleDbCommand = New OleDbCommand(“select * from product_registration”, Company)
The first argument is the SQL query statement which fetch all columns from the table and the second is the connection string. Before executing this we also need to open the concoction.
To print the rows we need another object called OleDbDataReader which help us to fetch row from command object and it works with following code
Dim reader As OleDbDataReader = _
cmd.ExecuteReader(CommandBehavior.CloseConnection)
Do While reader.Read
Console.WriteLine(reader.GetString(0))
Loop
reader.Close()
Company.Close()
Insert statement
All other SQL statements can be made possible with the OleDbCommand object.
Company.Open()
Dim s As String = TextBox1.Text
Dim cmd1 As OleDbCommand = New OleDbCommand(“insert into product_registration (pruduct_name) values(‘” & s & “‘)”, Company)
cmd1.ExecuteScalar()
Company.Close()
Saving record is possible with ExecuteScalar method and it will execute the insert statement.
OleDbData Adapter – DataSet, DataView.
OleDbDataAdapter class is the interface between database engine and visual basic, it is the bridge between backend and frontend. This class brings the concept like dataSet and DataView. We will discuss all these concepts
Dataset
DataSet represents the offline/ local view of the database tables, that means no data connection necessary for accessing the fetched Dataset collection.
DataSet object can fill with Fill Method of Adapter as follows
Dim adapter As OleDbDataAdapter = New OleDbDataAdapter(“select * from product_Registration“, Company)
Dim dataset As DataSet = New DataSet()
adapter.Fill(dataset, “table1”)
DataGridView1.DataSource = dataset
DataGridView1.DataMember = “product_Registration“
The dataset can be used to fill DataGrid view too.
Dim dataset As DataSet = New DataSet()
adapter.Fill(dataset, “table1”)
DataGridView1.DataSource = dataset
DataGridView1.DataMember = “product_Registration“
The dataset can be used to fill DataGrid view too.
DataView
DataView object as the name indicate provides the table view. It can be useful when interact with the table rows.
Dim dv As DataView
dv = New DataView(dataset.Tables(“product_Registration”))
adapter.Fill(dataset, “table1”)
Dim c As Integer
c = 0
Do While c < dv.Count
Console.WriteLine(dv(c).Item(0).ToString)
c = c + 1
Loop
I think you got the topic
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