Lucene Frequently Asked Questions

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    1. What is Lucene
    2. Where is Lucene Home page ?
    3. Who is Doug Cutting ?
    4. Where is the home site of this FAQ ?
    5. Where can I download Lucene ?
    6. Will Lucene work with my Java application ?
    7. Who maintains Lucene ?
    8. How much does it cost ?
    9. Is Lucene governed by the LGPL ?
    10. Where can I learn more about Lucene ?
    11. Are there any alternative to Lucene ?
    12. What are Lucene system requirements ?
    13. Do I need any third party library to use with Lucene ?
    14. Does Lucene has a web crawler ?
    15. Does Lucene store a full copy of the indexed documents ?
    16. I want to help, where do I sign ?


    1. What is indexing ?
    2. Where the index database is stored ?
    3. How do I perform a simple indexing of a set of documents ?
    4. How can I update the indexing of a document or a set of documents ?
    5. How can I delete a document or set of documents from an index ?
    6. How can I add document(s) to the index ?
    7. What the Document objects are used for ?
    8. What is a Field object and what are the possible field kinds ?
    9. How should I decide what field types to use ?
    10. Can I use Lucene to crawl my site or other sites on the Internet ?
    11. How can I extract the content of HTML pages ?
    12. How do I index other document types such as PDF and Word ?
    13. What are Analyzers and what are the differences between them ?
    14. Can I use the same Analyzer object again and again ?
    15. Why is it important to use the same analyzer type during indexing and search ?
    16. What Analyzer should I use ?
    17. Can I write my own custom analyzer ?
    18. I need an analyzer with functionailty that is not supported by Lucene token filters, what should I do ?
    19. Does the order of the token filters used by an analyzer matter ?
    20. I want to use a token filters that uses a word dictionary, are there any special considerations ?
    21. Can my token filter generate multiple tokens for a single input token ?
    22. How can I find the effect of an analyzer on a given text ?
    23. What is PorterStemmer and what it is good for ?
    24. What is index optimization and when should I use it ?
    25. What are Segments ?
    26. How can I make 'pig' also match 'hog' ?
    27. What is the Stop Filter ?
    28. What about non English and non Latin languages ?
    29. How fast is Lucene indexing ?
    30. How can I perform a long indexing without affecting ongoing searches ?
    31. Is Lucene index database platform independent ?
    32. When I recreate an index from scratch, do I have to delete the old index files ?


    1. What is searching ?
    2. What is a query ?
    3. How do I get a Query object to represent a given query ?
    4. What are 'terms' ?
    5. What is the syntax of queries parsed by the QueryParser class ?
    6. What is a term query ?
    7. What is a boost factor ?
    8. What is a phrase query ?
    9. What is a boolean query
    10. Can I use the same query object more than once ?
    11. How can I verify that the query structure I created is ok ?
    12. My documents have multiple fields, do I have to replicate a query for each of them ?
    13. What about partial matches and regular expressions ?
    14. Ok, I do have a Query object, how do I perform a search ?
    15. How do I get the hits and what information is available for each hit?
    16. What is filtering and how is it performed ?
    17. How can I restrict the number of hits ?
    18. How can I specify the starting position of the hit list
    19. How can I get hits only from a specific date range?
    20. Can I have multiple date values or multiple date fields ?
    21. Can I embed date values in regular text fields ?
    22. How can I implement paging in case the hit list is too long ?
    23. Are the search results deterministic ?
    24. How can I show a 'star' rating for each hit ?
    25. Are the searches case sensitive ?
    26. I searched for 'xyz' and could not find it, why ?
    27. How does Lucene handle numbers and special characters ?
    28. How can I search for 'any word', 'all words' or 'phrase' ?
    29. Will a search for 'cat' match 'cats' ?
    30. Can I define search aliases so 'dog' will also match 'pet' ?
    31. How does Lucene assigns scores to hits ?
    32. Does the position of the matches in the text affects the scoring ?
    33. Does the length of a field affects its scoring ?.
    34. How can I increase the score of certain document types ?
    35. How can I show excerpts with the hit results ? How about highlighting the matched words ?
    36. How can I show a cached version of the document with the matched words highlighted ?
    37. How can I perform a search on a subset of the documents ?
    38. How can I perform hierarchical searches
    39. How can I delete from an hierarchical index a subtree
    40. I have large documents, How can I reduce the overhead of reading them from the Index
    41. Can I modify the index while performing ongoing searches ?
    42. Can I hide certain documents from a user (for security reasons) ?


    1. I have a great question for this FAQ, where should I submit it ?
    2. How can I help maintaining this FAQ
    3. What are the copyright terms for using this FAQ ?

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