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LibrarySkills@UCL: Searching for information

A guide to search techniques and developing a search strategy for assignments, literature reviews and research.

What are wildcards?

Wildcards are symbols which you can iincorporate into your search. They can be used to stand in for characters in a search string. The symbols used vary between databases, but are often symbols such as the question mark ? hash, #, dollar sign $, asterisk *.

  • The optional wildcard replaces any character, or zero characters. If ? was the optional wildcard symbol:

searching for colo?r would retrieve color OR colour

  • The mandated wildcard replaces any one character. If $ was the mandated wildcard symbol:

searching for wom$n would retrieve woman or women

Some databases allow you to specify a certain number of characters.

Tips for using wildcards

  • Only use wildcards where they are helpful. If they don't enhance your search, or make it easier - leave them out! There is no benefit in using wildcards unnecessarily.
  • Symbols used do vary between databases. Always check the help pages for the database or search platform you are using.
  • Sometimes the database field you are searching influences how and whether wildcards are used.
  • Not all databases support wildcards.
  • Sometimes the use of wildcards, truncation or other symbols will affect or disable other automated search functions, for exampe automatic term mapping in PubMed or lemmatization in Web of Science.
  • The rules for how to use wildcards do vary between databases - for example, how many characters must preceded a wildcard; whether more than one wildcard can be used in the same word; how punctuation affects wildcards etc. Always check the help pages for the database or search platform you are using.