ADODB component causes access violation on Win7/Server 2008

Question

I have a piece of code written in Delphi 2005 that searches for a particular attribute on a user in LDAP. I get an access violation when this is run on either Windows 7 or Server 2008, but not on XP or 2003.

Function IsSSOUser(UserId: String): Boolean;
var
  S : string;
  ADOQuery : TADOQuery;
  ADOConnectionSSO: TADOConnection;
begin
  result := false;
  Setdomainname;
  ADOQuery := TADOQuery.Create(nil);
  ADOConnectionSSO := TADOConnection.Create(nil);
  try
    ADOConnectionSSO.LoginPrompt := false;
    ADOConnectionSSO.Mode := cmRead;
    ADOConnectionSSO.Provider := 'ADsDSOObject';
    ADOQuery.Connection := ADOConnectionSSO;
    ADOQuery.ConnectionString := 'Provider=ADsDSOObject;Encrypt Password=False;Mode=Read;Bind Flags=0;ADSI Flag=-2147483648';
    ADOQuery.SQL.Clear;
    try
      S := 'SELECT AdsPath, CN, SN, SSOguid FROM '''
           + LDAPString + ''' WHERE objectClass=''user'' and CN = ''' + UserId + ''' ';
      ADOQuery.SQL.Add(S);
      ADOQuery.Open;
      ADOQuery.ExecSQL;
      if trim(ADOQuery.FieldByName('SSOguid').AsString) = '' then
        result := false
      else
        result := true;
    except
      on e:Exception do
        if e.ClassType <> EOleException then
          Showmessage(format('[%s] Exception in IsSSOUser: [%s]',[e.ClassType.ClassName, e.Message]));
    end;
  finally
    ADOQuery.Close;
    ADOConnectionSSO.Close;
    ADOQuery.free;
    ADOConnectionSSO.free;
  end;
end;

This code works fine on Windows XP and Windows Server 2003, but I get an access violation on both Windows 7 and Server 2008. I see a number of threads online about how changes to ADODB interface can break things on downstream OSes, but I am seemingly having the opposite problem. I'm building on a Windows 7 machine and the code only works on previous versions of Windows.

Answer 1

You will have to add

AdoQuery.ParamCheck := false;

before your

ADOQuery.SQL.Add(S);

since your LDAPString may contains a colon (:) eg. "LDAP://...." which causes the query to try create a parameter object for it. In addition there is no need for ADOQuery.ExecSQL after ADOQuery.Open.