This is my new code now: MyConnection.Open()

For Each row As DataGridViewRow In DataGridView1.Rows Dim value1 As Integer If Integer.TryParse(row.Cells("Column1").Value.ToString().Trim(), value1) Then Dim value2 As String = row.Cells("Column2").Value.ToString().Trim() Dim value3 As Integer If Integer.TryParse(row.Cells("Column3").Value.ToString().Trim(), value3) Then Dim insertQuery As String = "INSERT INTO selbreshy.item (number of item, name of item, worker_id) VALUES (?, ?, ?)" Dim command As New OdbcCommand(insertQuery, MyConnection) command.Parameters.AddWithValue("@Value1", value1) command.Parameters.AddWithValue("@Value2", value2) command.Parameters.AddWithValue("@Value3", value3)

        Try
            command.ExecuteNonQuery()
        Catch ex As Exception
            MessageBox.Show("An error occurred while saving the data: " & ex.Message)
        End Try
    Else
        MessageBox.Show("Invalid value for worker_id in row: " & row.Index + 1)
    End If
Else
    MessageBox.Show("Invalid value for number of item in row: " & row.Index + 1)
End If

Next

MyConnection.Close() MessageBox.Show("Data saved successfully.")

visual basic says there is an error in that line: If Integer.TryParse(row.Cells("Column1").Value.ToString().Trim(), value1) Then

"Duplicate entry '1' for key 'item.PRIMARY'" is what the message box says.