November 22, 2010

AND, and, &

Alloway Librarians  want to remind library catalogue users that Boolean operators are at work for online catalogue keyword searches.  Boolean operators are words intended to help focus a search by eliminating some results, or by including others.  Common Boolean operators are AND, OR and NOT; and yes, these are case sensitive, so it does matter if the keyboard's Caps Lock is on or off.
For example you will get very different Keyword Search results for  matthew AND commentaries  and for  matthew and commentaries.
The former brings back 126 results, while the latter only 2!   That's because matthew AND commentaries produces results where both of those words  appear in the catalogue record. (Using the & symbol will produce the same results as AND. ) On the other hand, matthew and commentaries creates a search looking for the phrase "matthew and commentaries."  Matthew OR commentaries produces even more results: anything with either one of those words in the record.
Systems Librarian Shirley Lee offers some tips:
To use the Boolean operators AND, OR, NOT, you must type them in upper case letters, otherwise the system assumes it is a word to search for. You can also use a minus character (-) immediately before a word instead of NOT. For example, Bears -Chicago is the same as Bears NOT Chicago.  The results would exclude references to the football team as well as other entries where the words "Bears" and "Chicago" might appear together.
The AND or & operator is always implied between words unless you enclose the words in quotation marks to indicate that you want to perform a phrase search.  So, a keyword search  for "Chicago bears" would yield the same results as "Chicago AND Bears"
Hence, entering the keyword search terms:
Bud not buddy  will find the title: Bud Not Buddy
However, entering the search terms:  Bud NOT buddy will find only hits that contain the term Bud, but will omit those with the term buddy. Hence it will not find the title: Bud not Buddy.
Like most powerful tools, Boolean operators need to be used with care, but can produce excellent results when used well.
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