delphi sorting descending - delphi

Question

I’m trying to sort the records (in descending order ) and display the data in grid which is connected through datasource to the dataset Vw_EmpVacations
Here is the code, please tell me what I did wrong
By the way, the view is sorted descending according to start_date when I execute it in the database
Vw_EmpVacations.Active:=false;
Vw_EmpVacations.SQL.Text:='select * from Vw_EmpVacations where Branch_ID=:x and emp_id=:y and vac_id=:z order by Start_Date Desc ';
Vw_EmpVacations.Parameters[0].Value:=branch_ID;
Vw_EmpVacations.Parameters[1].Value:=emp_Id;
Vw_EmpVacations.Parameters[2].Value:=Vac_ID;
Vw_EmpVacations.Active:=true;
thank you

Answer 1

I will try to help you despite the fact that you are very sparse in details about your problem;-)
Please create a new VCL Forms Application - Delphi For Win32 project.
Then, replace the source of project with this code:
program SortTest;
uses
Forms, ADODB, DB, DBGrids;
var
qrySortTest: TADOQuery;
conSQL2005: TADOConnection;
dsSortTest: TDataSource;
grdTest: TDBGrid;
MainForm: TForm;
begin
Application.Initialize;
conSQL2005 := TADOConnection.Create(Application);
with conSQL2005 do
begin
Name := 'conSQL2005';
//Do not forget to change the connection string
ConnectionString :=
'Provider=SQLOLEDB.1;Integrated Security=SSPI;Persist Security In' +
'fo=False;Data Source=WODZU-LAPTOP\SQL2005S';
LoginPrompt := False;
Provider := 'SQLOLEDB.1';
Connected := True;
end;
qrySortTest := TADOQuery.Create(Application);
with qrySortTest do
begin
Name := 'qrySortTest';
Connection := conSQL2005;
CursorType := ctStatic;
SQL.Clear;
SQL.Add('SELECT '#39'Kowalsky'#39' as Surname, 25 as Age');
SQL.Add('UNION');
SQL.Add('SELECT '#39'Smith'#39', 38');
SQL.Add('UNION');
SQL.Add('SELECT '#39'Jensen'#39', 11');
SQL.Add('UNION');
SQL.Add('SELECT '#39'Doe'#39', 26');
SQL.Add('UNION');
SQL.Add('SELECT '#39'Clarke'#39', 45');
SQL.Add('ORDER BY AGE DESC');
Active := True;
end;
dsSortTest := TDataSource.Create(Application);
with dsSortTest do
begin
Name := 'dsSortTest';
DataSet := qrySortTest;
end;
MainForm := TForm.Create(Application);
MainForm.Position := poScreenCenter;
grdTest := TDBGrid.Create(Application);
with grdTest do
begin
Name := 'grdTest';
Parent := MainForm;
Left := 8;
Top := 8;
Width := 320;
Height := 120;
DataSource := dsSortTest;
TabOrder := 0;
end;
MainForm.ShowModal;
Application.Run;
end.
Remember to put correct connection string to your SQL Server, otherwise it will not work.
Run the test, does it show you rows sorted by Age column in descending order? If yes, then this is the place for you to start.
Replace the qrySortTest.SQL with your parameterless query and check if it works. If not, then the problem lies in your query not in the component setup.
Hope this helps.