sql1:='';
 sql1:='select * from orders where CustomerId= ' + QuotedStr(smdbgrid1.Fields[5].AsString);
              adoQuery1.SQL.Clear;
              adoQuery1.SQL.Add(sql1);
              adoQuery1.Open;
              if adoQuery1.Eof then //jika tidak ketemu atau tidak ada, lakukan insert data
                 begin
                 //proses simpan data
                 end
                else
                    begin
                    Application.MessageBox('Data sdh ada','Bintasy',mb_ok);
                    end;
 

@onsir:

 sql1:='select  from orders where CustomerId= ' + QuotedStr(smdbgrid1.Fields[5].AsString);
 

sql1:='select   from orders where CustomerId= ' + smdbgrid1.Fields[5].AsInteger;

sql1:='select * from orders where CustomerId= :custId';
..ParamByName('custId').AsInteger:=smdbgrid1.Fields[5].AsInteger

sql1:='select * from orders where CustomerId = :custID';
                          sql1:=sql1 + ' and EmployeeID = :emplId';
                          sql1:=sql1 + ' and OrderDate =  :ordDate';
                          sql1:=sql1 + ' and PurchaseOrderNumber = :poId';
                          sql1:=sql1 + ' and ProductID = :prodId';
                          adoQuery1.SQL.Clear;
                          adoQuery1.SQL.Add(sql1);
                          adoQuery1.Parameters.ParamValues['custId']:=smdbgrid1.Fields[15].AsInteger;
                          adoQuery1.Parameters.ParamValues['emplId']:=smdbgrid1.Fields[16].AsString;
                          adoQuery1.Parameters.ParamValues['ordDate']:=smdbgrid1.Fields[0].AsDateTime;
                          adoQuery1.Parameters.ParamValues['poId']:=smdbgrid1.Fields[5].AsString;
                          adoQuery1.Parameters.ParamValues['prodId']:=smdbgrid1.Fields[17].AsString;
                          adoQuery1.Open;