LibrarySkills@UCL: Searching for information

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.

• 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.