Search: Boolean operators
The 3 most important Boolean operators that can be used to search on the internet are AND, OR and NOT. These operators are used as conjunctions to combine or exclude search terms in a search, resulting in more focused and productive results. The use of these operators can significantly reduce or expand the number of results delivered. Boolean operators are useful to save time by searching for more targeted results that are better suited to your needs, eliminating unsuitable results.
Almost every search engine or database uses the Boolean operators AND, OR and NOT. In most search engines these operators are case sensitive and should be used in capitals.
How to use the Boolean operators:
AND: requires both terms to be taken into account in each result. If one of the terms is in the search result and the other is not, the item will not be included in the resulting list (limits the search).
Example: You are looking for documents that are about apples and pears (so both terms appear in the document). Your search = apples AND pears.
OR: the search result for each term separately or both search terms together will be displayed (broadens the search).
Example: You are looking for documents that are about apples or pears (at least one of these terms appears in the document). Your search = apples OR pears.
NOT: the first search term you enter will be searched and then all search results that contain the search term after the Boolean operator "NOT" will be deleted from the search result. (Be careful with the use, because this action to limit the search can be too exclusive and eliminate good search results).
Example: You are looking for documents that are about apples, but the term pears should not be used. Your search = apples NOT pears.
Alliant libraries. "What are Boolean operators?"
InfoNu. "Booleaanse operatoren"
Infovaardig. "Booleaanse operatoren"
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- Database search: how to use search terms? (Search / find)
Last modified Feb. 17, 2023, 2:12 p.m.