Refine and Narrow or Broaden a Search Topic Using Boolean Logic
Use Boolean operators to combine search terms in a database search. These operators [AND, OR, NOT] allow the searcher to broaden or narrow the search focus as necessary.
AND Searches
Use AND when combining different concepts or ideas within a search. An AND search means each concept or term ANDed together will be contained in the search results.
Use this Boolean operator to narrow the focus of a search and retrieve
records that are more relevant to the topic.
- "Children AND violence" narrows the search because it will retrieve only items that contain both terms.
OR Searches
Use OR to combine similar words [synonyms] or words with similar meanings. This search will retrieve records with either of the terms ORed together.
- "High schools OR secondary schools" broadens the search because it will retrieve items with either of these terms.
NOT Searches
A NOT search is similar to AND in that it narrows the focus of the search but it is getting rid of a concept or term rather than including one.
- "High schools not junior high schools" will narrow the search because it will eliminate records that include junior high schools.
