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    Boolean searches in Primo don't work as expected

    • Product: Primo
    • Product Version: All versions
    • Relevant for Installation Type: All types

     

    Symptom:

     

    When comparing search results with Boolean operators the numbers don't add up.

    For example:

    • Searching for A returns X records
    • Searching for B returns Y records
    • Searching for A AND B returns a number of records greater than  X or Y ( the greater number)

     

    Example:

    • Searching for 'documentary' returns 21,473 records
    • Searching for 'film' returns 477,172 records
    • Searching for 'documentary film' returns 24,102 records
    • Searching for 'documentary AND film' returns 21,300 records

    Explanation:

     

    Primo's search engine has a sophisticated algorithm which expends and alters queries so that the results returned will be relevant to the search.

    Such changes relate to searching for:

    • authors
    • synonyms
    • common misspellings
    • Phrase searching
    • Searching in full text of PCI records
    • Etc.

     

    The search engine algorithm builds a series of Boolean searches which increases the relevance of the results, as opposed to an SQL search, for instance, which works in a direct manner on the data.

    This is important in particular for searches in PCI where, due to its sheer size, a direct search (as SQL) would return an extremely large amount of records, all meeting the search query but  many of them may have low relevance to the end user.

     

    Conclusion:

     

    The results of different searches aren't necessarily comparable in a linear relation.

     

     


    • Article last edited: 18-Jan-2017