For investors who feel they still need the extra mile, specialist services such as provided by Kroll do not come cheap. 对于那些认为仍需要做出更多调查的投资者而言,德安华等机构提供的专业服务要价不菲。
Although the N extra selects were cut to1, this is only good when re-running the query on pojoA is cheap. 尽管N次额外的select减少到1次,但这只在重复运行pojoA的查询开销很低时才有好处。