else problem in asp.net

hi friends,

In if condition,

it checks only else part in runtime,

CommandText = "select * from empOrder By calldate desc limit 20 WHERE calldate > '" + Label1.Text + "' Order By calldate desc limit 20";


please correct this code.


OdbcConnection myConnection = new OdbcConnection(ConnectionString);

string CommandText = string.Empty;

if(Label1.Text == "" || Label1.Text == null)
{
CommandText = "select * from emp Order By calldate desc limit 20";
}
else
{
CommandText = "select * from emp Order By calldate desc limit 20 WHERE calldate > '" + Label1.Text + "' Order By calldate desc limit 20";
}
OdbcCommand myCommand = new OdbcCommand(CommandText, myConnection);

myConnection.Open();

GridView1.DataSource = myCommand.ExecuteReader();
GridView1.DataBind();

myConnection.Close();
thanks.