Verwenden Sie Parameter in Ihren Abfragen:
// C#
SqlCommand cmd = new SqlCommand("UPDATE Products SET description = @Description WHERE id = @ID");
cmd.Parameters.AddWithValue("@Description", "something");
cmd.Parameters.AddWithValue("@ID", 123);
Und das Äquivalent in VB.net:
// VB.net
Dim cmd As New SqlCommand("UPDATE Products SET description = @Description WHERE id = @ID")
cmd.Parameters.AddWithValue("@Description", "something")
cmd.Parameters.AddWithValue("@ID", 123)