function CreateCache(LOGGROUP $grp = NULL, $flags = 0)
{
$grp = $this->CheckGroup($grp, $flags);
$greq = $this->GetCachePostfix($grp);
/*
Older version
$cache = new CACHE(new GROUPRequest($greq), $rdr = NULL, $flags);
*/
$props = $this->req->props;
$props['db_group'] = $grp->gid;
$props['base_mask'] = $greq['db_mask'];
$req = new GROUPRequest($props);
unset($greq['db_mask']);
$cache = new CACHE($req, $this, $flags);
$cache->SetDefaultPostfix($greq);
return $cache;
}