[Lucene-java Wiki] Update of "LuceneFAQ" by UweSchindler

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The "LuceneFAQ" page has been changed by UweSchindler:
http://wiki.apache.org/lucene-java/LuceneFAQ?action=diff&rev1=151&rev2=152

Comment:
one more optimize

  Yes, you can.  Lucene is not limited to English, nor any other language.  To index text properly, you need to use an Analyzer appropriate for the language of the text you are indexing.  Lucene's default Analyzers work well for English.  There are a number of other Analyzers in [[http://lucene.apache.org/java/docs/lucene-sandbox/|Lucene Sandbox]], including those for Chinese, Japanese, and Korean.
  
  ==== Why do I have a deletable file (and old segment files remain) after merging? ====
- This is normal behavior on Windows whenever you also have readers (IndexReaders or IndexSearchers) open against the index you are optimizing.  Lucene tries to remove old segments files once they have been merged.  However, because Windows does not allow removing files that are open for reading, Lucene catches an IOException deleting these files and and then records these pending deletable files into the "deletable" file.  On the next segments merge, Lucene will try again to delete these files (and additional ones) and any that still fail will be rewritten to the deletable file.
+ This is normal behavior on Windows whenever you also have readers (IndexReaders or IndexSearchers) open against the index where a IndexWriter is open in parallel that does merges.  Lucene tries to remove old segments files once they have been merged.  However, because Windows does not allow removing files that are open for reading, Lucene catches an IOException deleting these files and and then records these pending deletable files into the "deletable" file.  On the next segments merge, Lucene will try again to delete these files (and additional ones) and any that still fail will be rewritten to the deletable file.
  
  Note that as of 2.1 the deletable file is no longer used.  Instead, Lucene computes which files are no longer referenced by the index and removes them whenever a writer is created.