title: Text indexing algorithm
body: <p>I am writing a C# winform application for an archiving system. The system has a huge database where some tables would have more than 1.5 million records. What i need is an algorithm that indexes the content of these records. Mainly, the files are Microsoft office, PDF and TXT documents. anyone can help? whether with ideas, links, books or codes, I appreciate it :)</p>
  
  <p>example: if i search for the word "international" in a certain folder in the database, i get all the files that contain that word ordered by a certain criteria such as relevance, modifying date...etc</p>