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Boolean operators

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Discover how to use Boolean operators to narrow or broaden your WorldCat index search.

Use the Boolean operators shown in the following table for combining search terms to narrow or broaden searches: 

Boolean operator Notes Example
Connexion/FirstSearch WorldShare and WorldCat Discovery
and AND
  • Finds all terms anywhere in a record
  • Can omit for simple searches when just one index label is used or where no other boolean operator is used
  • Can use the plus sign (+) in place of and/AND
 su:wom?n and ti:history and gc:new york and yr:1970
or OR Finds any single term or all terms pn=woolf, virginia or pn=woolf, leonard and yr:1900-50
not NOT
  • Excludes the term that follows not
  • Can use the minus sign (-) in place of not/NOT
 ti=civil war not su:battle not gc=united states

Boolean searches are processed in left to right order.

Guidelines

  • Type operators between search terms to combine them.
  • Some complex Boolean searches in the WorldCat.org and WorldCat Discovery interfaces are not supported. These types of queries are prevented to enhance the search infrastructure's overall performance. WorldShare Record Manager and FirstSearch continue to support this index.
  • Do not use for browsing (scanning indexes).
  • Do not truncate a music publisher number or Government Document Number in a combined search; type the complete number.
  • Boolean searches can be nested using parentheses — ut:(civil w1 war) and (battlefield w1 command*)
  • For Word searches, if you do not want the system to use these words as operators, enclose the word in quotation marks. For example, to search for the title Neighbors Near and Far which includes near and and, normally treated as operators, type ti:neighbors "near" "and" far.