linux命令同一位置显示差异的事情

Question

我在相同的位置使用命令ls，但显示差异。

[tiankonguse /usr/local/services/video_sphinx-1.0]# pwd;ls -a;ls -a ../video_sphinx-1.0/
/usr/local/services/video_sphinx-1.0
.  ..  bin  conf  etc  var
.  ..  conf  etc  incSphinxIndex.sh  indexer  search  searchd  syncCoverToSphinx.py

[tiankonguse /usr/local/services/video_sphinx-1.0]# cd ../video_sphinx-1.0/
[tiankonguse /usr/local/services/video_sphinx-1.0]# pwd;ls -a;ls -a ../video_sphinx-1.0/
/usr/local/services/video_sphinx-1.0
.  ..  bin  conf  etc  var
.  ..  conf  etc  incSphinxIndex.sh  indexer  search  searchd  syncCoverToSphinx.py