FROM BOBST LIBRARY

Finding the Needle in the Haystack:
Tips for Searching Databases Effectively

Claire Gabriel

[Ed: Links to web pages and/or e-mail addresses which have become inactive since the publication of this article have been enclosed in curly brackets { }. Replacement links have been provided where possible.]

CD-ROM periodical indexes are among the most popular resources in Bobst Library. With CD-ROMs and other electronic databases, researchers can quickly and efficiently locate citations to magazine and journal articles in a wide variety of subjects.

Bobst's three reference centers specialize in different subjects. Humanities and general reference resources can be found on the main floor; government documents, social-science and business materials are housed on the sixth; science, medicine, and technology resources are located on the ninth. Relevant electronic indexes are available in each of these reference centers. For example, the MLA International Bibliography, which focuses on literature and linguistics, is on the first floor, while social-science titles like Psychological Abstracts are available on the sixth (for the record, abstracts are brief summaries). In addition to these specialized items, each reference center provides access to a few multidisciplinary indexes, including Periodical Abstracts and Dissertation Abstracts.

In this article, we'll explore some features common to most databases, and outline techniques which can be applied to a wide range of databases, from online library catalogues like BobCat to the myriad CD-ROM and online systems available in the Library's reference areas.

Database Lingo

Databases are made up of records (see example), and records are made up of fields. Fields in our example include title, author, abstract, and subject, among others. If we simply enter words at the search screen, we'll retrieve a list of records containing those words anywhere they appear in the record. If our terms are very general, we'll retrieve far too many items, and many will not be relevant to what we're researching. There are two important techniques for refining our database searches: first, we'll limit our search to certain fields, and then we'll combine terms using the Boolean operators and and or. That's it for the jargon, promise! (For more database terminology, see Glossary of Database Terms.)

Limiting a Search to Specific Fields

Although the specific commands differ from index to index, it is always possible to search for words within fields. If a word appears in the title of an article, or is identified as the article's subject or descriptor (see the glossary sidebar), it is more likely to be relevant than the chance inclusion of the same term within the article's abstract or other less relevant field.

We can improve the accuracy of a search in Psychological Abstracts and eliminate many "false hits" by limiting our search to the descriptor field. Let's say we're researching the psychological correlation between job satisfaction and salary. At the search prompt, we might type (using either capital or small letters)
salaries in de and job satisfaction in de
This will yield citations that address both facets of our research. The phrase
in de
specifies that both terms must be located in the descriptor field.

Periodical Abstracts uses the term subjects rather than descriptors. To find articles on water pollution and legislation, we would enter
su(water pollution) and su(legislation)
being sure not to leave a space between su and the parentheses around the terms we're searching for.

Both Periodical Abstracts and Psychological Abstracts provide an online list of subject headings from which you can select terms for your searches. In Periodical Abstracts, press the F6 key, select subjects and begin typing possible search terms; in Psychological Abstracts, press the F9 key for the online thesaurus.

The limit feature is also useful for locating articles by a particular author. In Periodical Abstracts, the code au is used to specify the author field -- as in au(chomsky, noam). If you're not sure of an author's name, press F6, select authors, and begin typing the last name. In Psychological Abstracts, press F5 and type in the author's name (again, last name first). Then press s for select and f for find to identify articles by that author.

Combining Keywords

To make an even more precise search, combine keywords using and; to broaden the search possibilities, combine keywords using or. With some care, you can use both and and or in one search. Let's look again at our Periodical Abstracts example about water pollution. If we want to locate articles that deal with both legislation and government regulation, we can formulate the search as follows:
su(water pollution) and su(legislation or regulation)
In this case, the keywords legislation and regulation (linked by or) broaden the search to citations concerning either legislation or regulation that also deal with water pollution. But note that when using both and and or in one search statement, parentheses must be included to indicate the intended relationship between keywords.

Similarly, our search for materials on salaries and job satisfaction can be expanded. If we want to expand our search to include materials on salaries and job performance, we would formulate the search statement in this way:
salaries in de and (job satisfaction in de or job performance in de)
This will yield citations to articles and other materials dealing with both job performance and job satisfaction as related to salary.

A Few More Details . . .

In many databases, including Periodical Abstracts, citations are displayed in reverse chronological order; that is, the most recent citations appear first. Keep in mind that just because these sources are electronic does not necessarily mean that they offer up-to-the-minute information. Like printed indexes, CD-ROMs are generally updated only periodically. Online databases, by contrast, are often updated much more frequently. In news-related databases where timeliness is essential, some in fact are updated daily.

Most databases allow truncation of words. This simply means that we can look for anything that begins with a certain "root" word. Some databases use the asterisk, others the question mark, and still others the pound sign (#) as a truncation symbol. As an example, in Psychological Abstracts we would type addict* to retrieve citations dealing with addicts, addiction, or addictive behavior. Since most databases are designed to be user-friendly, if we look around the screen there is usually some way to find out these specific details without too much trouble. Help sheets for each database are located near the computer networks in each reference center.

Since most of Bobst's periodical indexes on CD-ROM are produced by just a few electronic publishers, skills learned in one database will easily transfer to another. For instance, searching techniques learned in Periodical Abstracts can be used in Dissertation Abstracts and the New York Times Ondisc, since all are produced by the same company. Similarly, the MLA Bibliography and Psychological Abstracts share a common search interface. With a little practice, you can become an expert searcher of the databases you'll need to use regularly. [ C ]

Claire Gabriel was Librarian for U.S. and World History at Bobst Library at the time of this article's publication.
{gabriel@is.nyu.edu}

Posted 20 May 1996. Revised 24 May 2004.