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Discovery Tools @ UMD

News, tutorials, and tips for using discovery tools at UMD.

Booleans, Truncation, and Wildcards

Like any other library database, WorldCat UMD offers Boolean searching (and, or, not), truncation symbols, wildcards, and phrase searching.

Boolean Operators


The following table provides a good summary of Boolean operators and phrase searching. Note, AND, OR, and NOT must:be in all-caps:


Boolean chart

Truncation Symbols/Wildcards


  1. The asterisk (*) is the truncation symbol. (e.g., secur* matches secure, security, securities, etc.).
  2. Pound (#) is a wild card symbol representing one single character. (e.g., anders#n matches Anderson, Andersen).
  3. Question mark (?) is a wild card symbol representing any number of characters. You can also specify how many characters to match by adding an Arabic numeral after the question mark (e.g., bu?2er matches butter, butler, burner).

Searching With OCLC Indexes

Index Labels

If you want to get more precise searching you can use index labels. This technique is similar to using the drop-down menus in the advanced search. In fact, anything you can do in the advanced search can also be replicated in the single search box by using index labels. In addition, and importantly, the index labels offer many more choices that what you get from the advanced search screen.

You can get an idea of how index labels work by doing an Advanced Search and then examining the search box in the results screen. This search:

Advanced Search example

is the same as this one:

basic search example

You can find a complete list of supported indexes here.

Some useful ones:

  • am: access method (such as a url)
  • au: author name
  • b8: searches by University of Maryland Library and location (for example: b8:UMAA searches for items in UMD's Achitecture library)
  • bn: ISBN
  • in: ISSN
  • ln: language (e.g., ln:English)
  • no: OCLC Number
  • nu: call number
  • pb: by publisher name
  • se: series titles
  • sn: standard number (ISBN, ISSN, LCCN, and many others)
  • su: subject term
  • ti:  title

Index Search Types ( : vs = )

OCLC index searching generally supports two "types" for searching, word searching and phrase searching, which are denoted by punctuation used when searching, colon and equals sign respectively. Not all indexes support both types of searching, so you may want to double check with the documentation when first trying out index searching. Phrase type searching seeks only returns records matching the exact phrase in your query while word type searching will return records matching any part of your query. For example au=Shakespeare, William returns records where the author is an exact match for Shakespeare, William, but au:Shakespeare, WIlliam will return records where the author field contains either "Shakespeare" or "William". Phrase searching can be helpful for creating targeted searches, but it is important to be mindful that it is a strict search. For example, if you're searching for Edgard Allen Poe's Complete Stories and Poems and you run the search ti=Complete Stories and Poems, the copies of the book owned by the libraries will not be returned because the title is not an exact match (for example, one of our copies of the book is titled Complete Stories and Poems of Edgar Allen Poe, which would not be returned by that phrase search because it has additional words in the title). See how the results are different when using the word search instead of the phrase search.