I ran the code below that adds a column to an SQL table.
I refreshed Data Sources, but, the new column does not appear.
I refreshed Server Explorer and the new column does not appear.
I tried running the code again and I got:
"Column names in each table must be unique. Column name 'CaseNbr' in table 'Patient' is specified more than once."
so the column did actually get added, but, I can't see it.

Imports System.Data.SqlClient
Public Class Form1
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Dim sqlConnection As New System.Data.SqlClient.SqlConnection("Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\Patient.mdf;Integrated Security=True;User Instance=True")
Dim str As String = "ALTER TABLE Patient ADD CaseNbr Varchar(50)"
Dim command As New System.Data.SqlClient.SqlCommand(str, sqlConnection)
sqlConnection.Open()
command.ExecuteNonQuery()
sqlConnection.Close()
Close()
End Sub
End Class