Keyword Files
There are two keyword files; the WORDLIST file which contains one instance of each keyword, and the KEYWORDS file which contains each keyword and a pointer to the item that the keyword is associated with.
Each record in the wordlist file also contains the number of appearances of the keyword in the keywords file. This allows the search engine to optimize the search process by knowing how many instances of each keyword are in the file and starting “and” searches based on the smaller count.
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Keyword File (File 147)