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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




    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)



    • 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



    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.




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



    • Article last edited: 18-Jan-2017