Runtime connection

data_module.pas

// Returns a full path to the current dir
function currentDirPath():String;
begin
  result:=extractFileDir(expandFileName('anything'));
end;

// Makes connection string at runtime.
// it's necessary because delphi don't understand relative paths.
procedure TDataModule.ADOConnectionBeforeConnect(Sender: TObject);
begin
  ADOConnection.ConnectionString:='Provider=Microsoft.Jet.OLEDB.4.0;User ID=Admin;Data Source=' + currentDirPath() +
    '\db\Library.mdb;Mode=Share Deny None;Extended Properties="";Jet OLEDB:System database="";Jet OLEDB:Registry Path="";' +
    'Jet OLEDB:Database Password="";Jet OLEDB:Engine Type=5;Jet OLEDB:Database Locking Mode=1;Jet OLEDB:Global Partial Bulk Ops=2;Jet OLEDB:Global Bulk Transactions=1;' +
    'Jet OLEDB:New Database Password="";Jet OLEDB:Create System Database=False;Jet OLEDB:Encrypt Database=False;Jet OLEDB:Don''t Copy Locale on Compact=False;Jet OLEDB:Compact Without Replica Repair=False;Jet OLEDB:SFP=False';
end;