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IFS 2021-S104 Through the Looking Glass (Christiansen)

Why use Boolean operators?

Most library databases use Boolean operators (ANDOR, and NOT). 

Use them to narrow or broaden search results.

  • AND for records that include both terms (narrows search)
  • OR for records that include either term (broadens search)
  • NOT to exclude irrelevant concepts (narrows search)

Example:

Iran AND China AND (energy OR petroleum OR oil) 

Adapted from SAIS Library, Johns Hopkins Univ. "Database Search Tips" Guide

    Boolean Operators

    Using AND:

    • narrow results
    • ALL terms must be in each search result

    Note: in most, but not all, databases, the AND is implied. For example, Google automatically puts an AND in between search terms.

    Example:  renewable energy AND China


    Using OR:

    • connect similar concepts (synonyms)
    • broaden results (ANY of the terms can be in the search results.)

    Example:  renewable energy OR solar OR wind

     


    Using NOT:

    • exclude words from search
    • narrow the search

    Example:  peacekeeping NOT United Nations


    Adapted from SAIS Library, Johns Hopkins Univ. "Database Search Tips" Guide