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Choosing and Using Library Databases

Phrase versus Keyword Searching

Determine whether the database considers multiple words as a single phrase or a combination of words in any order. If you want to change the default, there are some standard ways to do so:

  • To switch from keyword to phrase searching, put phrases in quotes.
  • To switch from phrase to keyword searching, try putting the individual words in separate boxes (if available) or separate them with the word "and". (See Boolean searches.)

If those techniques don't work, check the database help for options.

Example of how you get different results with keyword searches...

JSTOR search for national ice cream day (no quotes). 111,127 search results

... versus phrase searches

JSTOR search for national ice cream day (in quotes). 1 search result

Limit Options

Most databases allow you to narrow your search by selecting specific dates of publication, languages, or publication types. Databases that mix scholarly and non-scholarly content often let you limit to scholarly sources.

Some databases apply limits before the search, usually on the advanced search screen:

Search limits on a sidebar, including Full Text, References Available, Scholarly Journals, Source Types, Subject, Publication, Company, Geography, NAICS/Industry.Search limits on a search screen, including Full Text, Scholarly Journals, Document Type, References Available, Published Date, Publication Type, and Language.

While others apply limits after the search, usually in options in a side column:

A few allow both options. These examples are actually both from Academic Search Complete.

Specialized subject databases are also likely to have limits unique to the discipline:


Specialized Search Limits

Historical Abstracts and America: History & Life
  • Dates the article is about
Engineering Village
  • Numerical data (mass, frequency)
  • Chemical data (element),
  • Astronomical object
  • Methodology
  • Age group
  • Population
Bibliography of Asian Studies
  • Country

Limiting to Full Text

Databases that contain a mix of full-text and index-only content, often have a checkbox limit for full-text only—like both of the pictured examples here. Don't use it! The problem is that even if this database doesn't have the full-text online, some other database may. That's what UC-eLinks is for!

Wildcards and Truncation

wildcard search

will find

wom?n woman, women

Wildcards are special characters which stand for ANY letter in the alphabet.

The exact symbol used to represent a single variable letter varies from database to database, but common signs are ?, *, #, and $.

truncation search

will find

psych* psychology, psychological, psychiatry, psychotic, etc.

A truncation symbol is a specific type of wildcard used to represent any number of letters (including zero) at the end of a word. An asterisk is the most common truncation symbol, but check the database help if it doesn't work.

Not all search engines allow wildcards or truncation. (The most famous example is Google.) And some do automatic truncation, automatically searching for common variants of each word, especially plurals.

Boolean Searches

Boolean Operator
The shaded portion includes all the results for "cat AND dog."
Boolean Operator
The shaded portions include all the results for "cat OR dog."
Boolean Operator
The shaded portion includes all the results for "cat NOT dog."

Many databases allow Boolean searching.