كيف اعمل برنامج multi-user 'صلاحيات المستخدمين' بواسطة قاعدة بيانات؟

كود :

const
    AUTH_ADD_NEW = 1;                            // إضافة بيانات
    AUTH_MODIFY = 2;                                // تعديل بيانات
    AUTH_DELETE = 3;                                  // حذف بيانات
    AUTH_PRINT_INVOICE = 4;                  // طباعة فاتورة
    AUTH_PRINT_SALES_REPORT = 5;    // طباعة تقرير المبيعات
    AUTH_BACKUP = 6;                               // نسخ احتياطي
    AUTH_RESTORE = 7;                             // استعادة بيانات
    // إلخ

كود :

var
    UserAuths: string;

كود :

procedure GiveAuthority(var Authorities: string; Index: Integer);
procedure DeleteAuthority(var Authorities: string; AuthCount, Index: Integer);
procedure GiveAllAuthorities(var Authorities: string);
procedure DeleteAllAuthorities(var Authorities: string);
function UserHasAuthority(Authorities: string; Index: Integer): Boolean;

كود :

procedure GiveAuthority(var Authorities: string; Index: Integer);
var
    Auths: string;
    AuthLen: Integer;
begin
    if Index < 1 then
        Exit;

    Auths := UpperCase(Trim(Authorities));

    if Auths = 'A' then
        Exit
    else if Auths = 'N' then
        Auths := '';

    AuthLen := Length(Auths);

    if Index <= AuthLen then
        Auths := StuffString(Auths, Index, 1, 'T')
    else
        Auths := Auths + StringOfChar('F', Index - AuthLen - 1) + 'T';

    if Pos('F', Auths) = 0 then
        Authorities := 'A'
    else
        Authorities := Auths;
end;

procedure DeleteAuthority(var Authorities: string; AuthCount, Index: Integer);
var
    Auths: string;
    AuthLen: Integer;
begin
    if Index < 1 then
        Exit;

    Auths := UpperCase(Trim(Authorities));

    if Auths = 'N' then
        Exit
    else if Auths = 'A' then
        Auths := StringOfChar('T', AuthCount);

    AuthLen := Length(Auths);

    if Index <= AuthLen Then
        Auths := StuffString(Auths, Index, 1, 'F')
    else
        Auths := Auths + StringOfChar('F', Index - AuthLen - 1) + 'F';

    if Pos('T', Auths) = 0 then
        Authorities := 'N'
    else
        Authorities := Auths;
end;

procedure GiveAllAuthorities(var Authorities: string);
begin
    Authorities := 'A';
end;

procedure DeleteAllAuthorities(var Authorities: string);
begin
    Authorities := 'N';
end;

function UserHasAuthority(Authorities: string; Index: Integer): Boolean;
var
    Auths: string;
    AuthLen: Integer;
begin
    if Index < 1 then
        Result := False
    else begin
        Auths := UpperCase(Trim(Authorities));
        AuthLen := Length(Auths);
        if Auths = '' then
            Result := False
        else if Auths = 'N' then
            Result := False
        else if Auths = 'A' then
            Result := True
        else if Index > AuthLen then
            Result := False
        else if Copy(Auths, Index, 1) = 'T' then
            Result := True
        else
            Result := False;
    end;
end;