Here's why this could happen: the metadata update would erase any reference to the original data block(s), but would point to data block(s) on disk that were never filled with data.

出现这种情况的原因如下：元数据更新删除了对原先数据块的任何引用，却指向磁盘上没有填充过数据的数据块。

youdao

Pick the block type from the drop-down, set its position in the column, enable it for display, save it by pressing CTRL + s, and close it.

您可以从下拉菜单中选择块的类型，设置它在列中的位置，并启用显示它，然后使用CTRL + S进行保存并关闭这个页面。

youdao

The company is seeking a far-reaching order that would block the plaintiffs from collecting on their judgment in the U. S. -or anywhere else.

这家公司正在寻求得到一个影响深远的法院令，阻止原告在美国或者其它任何地方执行他们的裁决。

youdao

On the one hand, there is Iran and its allies in the so-called "resistance" block, including Syria, the Palestinian group Hamas and Lebanon's Hezbollah.

VOA: standard.2010.03.18

It's just a little block of memory in RAM, you know, that represents four bytes, 32-bits and the Number Two is currently in it.

它只是一小块内存块，它表示4个字节，32位,那个数字2就存储在里面。

哈佛公开课 - 计算机科学课程节选

That says it's in here. It's in this tri-block. It raised an exception, but it wasn't and I O error.

这在这里它是一个try程序块,它报出异常，但他不是io错误。

麻省理工公开课 - 计算机科学及编程导论课程节选

Barrichello, who finished eighth, was later excluded from the official results by the stewards because of a technical irregularity on the car's skid-block.

BBC: Hakkinen leads McLarens home

The hotel's one-block proximity to the Technopark tram station puts it within a half-hour ride of the airport and within steps of the nightclubs, cafes and corporate towers sprouting up on every corner.

BBC: Business trip: Zurich

Villa saw another hat-trick opportunity go begging when Sergio Mendoza's brilliant last-ditch block prevented him from tapping in, but Spain probably already had one eye on Friday's crunch tie against Chile in Pretoria.

BBC: Spain 2-0 Honduras