ODP.NET - Retrieving a Single Row of Information Using OracleDataAdapter
In the previous example, we worked with a set of rows in the DataTable object. Now, we shall work with a particular row using the DataTable object. The following code accepts an employee number from the user and gives you the details of that employee:
Sample Code
Imports Oracle.DataAccess.Client Public Class Form3 Private Sub btnGetEmployee_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnGetEmployee.Click 'create connection to db Dim cn As New OracleConnection("Data Source=xe _ User Id=scottPassword=tiger") Try Dim SQL As String 'build the SELECT statement SQL = String.Format("SELECT ename, sal, job FROM emp WHERE empno={0}", Me.txtEmpno.Text) 'create the dataadapter object Dim adp As New OracleDataAdapter(SQL, cn) 'create the offline datatable Dim dt As New DataTable 'fill the data table with rows adp.Fill(dt) 'clear up the resources and work offline adp.Dispose() 'check if it has any rows If dt.Rows.Count > 0 Then 'extract the details Me.txtEname.Text = dt.Rows(0)("ename") Me.txtSal.Text = dt.Rows(0)("sal") Me.txtJob.Text = dt.Rows(0)("job") Else 'display message if no rows found MessageBox.Show("Not found") End If Catch ex As Exception 'display if any error occurs MessageBox.Show("Error: " & ex.Message) 'close the connection if it is still open If cn.State = ConnectionState.Open Then cn.Close() End If End Try End Sub End Class
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Once the DataTable object is filled using OracleDataAdapter, we can directly retrieve a particular row using the row index. Once the row is fetched, we extract column values by providing column names for the rows as follows:
Me.txtEname.Text = dt.Rows(0)("ename")
Me.txtSal.Text = dt.Rows(0)("sal")
Me.txtJob.Text = dt.Rows(0)("job")
The output for the above code would look similar to the following figure:
Tutorials 
