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  with dm.ASQLite3Query1 do
  begin
    close;
    sql.clear;
    sql.add('insert into student values(:id,:username,:telephone,:address,:state)');    //Ôö¼Ó
    dm.ASQLite3Query1.Params.ParamByName('id').Value:=strtoint(id_edit.Text);
    dm.ASQLite3Query1.Params.ParamByName('username').Value:=username_edit.Text;
    dm.ASQLite3Query1.Params.ParamByName('telephone').Value:=strtoint(phone_edit.Text);
    dm.ASQLite3Query1.Params.ParamByName('address').Value:=address_edit.Text;
    dm.ASQLite3Query1.Params.ParamByName('state').Value:=state_edit.Text;
    ExecSQL;

    open;


  showmessage(dm.ASQLite3Query1.SQL.Text);
  end;
end;


procedure Tmain.select_buttonClick(Sender: TObject);
var
sql:string;
begin
with dm.ASQLite3Query1 do
begin
  close;
  sql.clear;
  sql.add('select * from student where id='''+id_edit.text+'''');