Social Work *: How does the database understand my keywords?

Randall Information Center | USC School of Social Work

Boolean Operators

What are Boolean Operators?

Boolean operators are used by databases to focus searches. Three boolean operators are most recognized by database: AND, OR, NOT. When using the operators, use them in all CAPS.


  • Use AND to tell the database that your search results must include both or all of your keywords
  • It helps to narrow your results by combining keywords
  • It helps when searching a broad topic, to retrieve fewer results 
  • Example: higher education AND online learning will retrieve results that include are relevant to higher education in relation to online learning


  • Use OR to connect two or more similar concepts

  • It helps to broaden your search and retrieve more results

  • When using this operator, not all results will contain both concepts

  • Example: online learning OR distance education


  • Use NOT to exclude concepts from your search
  • It helps to narrow your search because it excludes concepts
  • It tells the database to ignore results related to a keyword
  • Example: online learning NOT "graduate school" will retrieve results that are relevant to online learning but exclude all results that are related to graduate school