Online Database Search Fundamentals

**crossposted at Literature Review for Library Techs**


This will be the first of many posts on the subject of search as it relates to library reference staff.  It is an area that fascinates me.  This literature review will examine some of the search strategies that you can employ in tracking down information on the databases.  It is intended to be an introduction to online database searching.

Search Strategies

Generally speaking, there are two ways for reference staff to approach a patron’s query that requires a search.

The specific-to-general approach is useful where the user has a specific topic in mind, and wishes to find similar topics (Bopp and Smith, 111)(Walker and Janes, 89).  An example could be where the patron knows the author of an item on a particular topic, and would like to find works by other authors on the same topic.  From this knowledge, you can locate one of the records by the author on the subject, and then click on one of the subject headings to find all other works with that heading.  If not enough results are gained from the initial query, keywords can be added from controlled vocabularies or titles (Bopp and Smith, 112), provided there is an “ANY” or an “OR search option.  As well, citations to which the author has referred can be used as the initial query.

If a specific topic is sought but not known, then you want the general-to-specific approach.  You need to determine the correct level of specificity required (Bopp and Smith, 112).  These can be found by consulting a subject thesaurus.  Bopp and Smith use the example of Medical Subject Headings online, where a tree structure is provided which will show the results from general to specific.  Though this can be done with Library of Congress Subject Headings as well, Bopp and Smith recommend more specialized databases.  Cross-references that are available to determine synonyms and related terms can be helpful as they increase the number of possible entry points for the searcher.

Cassell and Hiremath (48-52) suggest a five stage approach to developing a database search strategy.

  • Step 1 involves identifying the research topic.  They suggest writing out the topic as either a full sentence or a list of topics.  They further suggest refining the topic by using worksheets that can be accessed online.
  • Step 2 would involve identifying the appropriate database, whether is a general database, or a specific database focussing on one subject.
  • Step 3 suggests becoming familiar with the chosen database, what are the Boolean operators that are used, how the searches can be limited by various parameters
  • Step 4 recommends switching to a subject search based on the controlled vocabulary list if a limited keyword search doesn’t produce desired results.  You can pull a subject from the list, or from the individual records of your results.
  • Step 5 involves evaluating the results by looking at their number and quality.  If there are less than ten, they may be too stringent, while if there are over 200, they are probably not targeted enough.
  • Step 6 suggests preserving the results in some way.  They could be printed.  Alternatively, there are often other ways available to save the results you want, such as putting them in a folder provided by the database, saving them to a flash drive, or emailing them to yourself.

Search Manipulation

In a database, it is important to understand how search engines work, and how you can manipulate them.  It is helpful to use Boolean logic to formulate your search query (Bopp and Smith, 126-127)(Ford, 35-36)(Walker and Janes, 83).

Boolean logic, developed by the 19th century mathematician George Boole, uses what is known as logical operators to target the search.  The main ones which are used are AND, OR, and NOT.  With the OR function, there are more than one criteria, and results will show for items that contain either one or the other criteria.  In the case of the AND function, only results that contain all of the listed criteria will show.  Regarding the NOT function, results that we want to avoid will be excluded from a search.

Bopp and Smith talk about the importance of context in a search query (115).  In a case where a general term such as ‘psychological stress’ is searched for on a general database, you may receive too many hits for your purposes.  Therefore, they advise that you can add context to the search by adding a Boolean AND, as well as a more specific term within ‘psychological stress,’ such as ‘role conflict.’  In the case of a more specific database such as PSYCInfo, a general term is unnecessary.

Truncation is another method of manipulating searches (Bopp and Smith, 128-129)(Ford, 36).  On many databases, you can type the first part of a word, and then add a symbol, such as ‘?’ or ‘*’, to allow for more variations of the word.  For example, ‘librar’* could provide results such as ‘library,’ ‘libraries,’ and ‘librarian.’

Also, on a research database, there should be several other ways to shape your search.  On EBSCOhost for example, you can limit or expand searches by

  • Results that have full-text
  • Results from a certain range of publication dates
  • Types of images that are present in the results
  • A keyword in the publication name, and whether or not it’s peer-reviewed and/or has references
  • Special limiters that are specific to the index being searched, such as publication type, document type, language, and number of pages
  • Use SmartText searching where you can search for a chunk of text to search for results
  • Words related to your search term
  • Within the full text of articles
  • Searching across indexes within the EBSCOhost family

Proximity operators are an extension of Boolean searching that are concerned with the proximity of one word or term with another (Bopp and Smith, 133-134)(Ford, 37).  For example, on many databases, you can find a word within two or more words, or near a word, using the operators ‘n’ and ‘w (Smith)(Ford, 37).  ’  For example, ‘John w2 Kennedy’ could mean ‘John Kennedy’ or ‘John F Kennedy.’  It must be in that order though, and would not find ‘Kennedy John.’  In the case of ‘n’, the order in which the words appear are not important.  Thus, you could have influence ‘art n2 film’, and it could mean ‘art on film’, or ‘film art’, as long is it is within two words.  Another example is nesting, which resembles algebraic formulas where you calculate what is in the parentheses first, and then calculate this total with another search word or term (Ford, 37).  For example, ‘fiction AND (science fiction OR fantasy)’ as a subject search would give you any item that is fiction and that is either science fiction or fantasy.  ADJ means that one word will be followed by the next.  An example would be ‘shopping ADJ mall’ for ‘shopping mall.’  Quotations around the words would serve the same function.

Ford (39) makes the point that it is always important, and the mark of a true professional, to refine your search query based on your initial results (also see Walker and Janes, 83).  For example, if there are too few results, you can re-examine the original question, and come up with additional terms you could add using the OR function.  Conversely, if there are too many results, there are several ways you can restrict your search.  These include consulting the thesaurus to determine more specific search terms, adding terms to the search using the AND function, or limiting it by date range or language

Federated Searching and Beyond

In recent years, the ability to search across databases has developed.  In the early 2000s, federated searching software was developed.  It allows the searcher to search across multiple search tools simultaneously (Bopp and Smith, 151)(Curtis and Dorner).  On the surface, it is a timesaver.  As wonderful as this sounds, there are some limitations that have been noted (Fagan).  For example, Bopp and Smith note that there are limitations in using one system to search across other systems that don’t “support the native system’s capabilities in the cross-search environment.” As well, some features that have been used in single databases, such as controlled vocabulary and exploding subject headings, aren’t extended to federated search (Stern), as well as the searching of data being done in real time.  Stern describes the harvesting approach, which means that data from host platforms is captured and then harvested into one single index.  It basically means that searches could be done on a larger scale than would be possible under real-time searching.


There is no single best way to approach a database search.  It will depend on the needs of the patron.  A general-to-specific approach is used where the patron has a single topic in mind, and want to find similar topics.  A specific-to-general approach is used where the specific topic is sought but not known.  To the degree that the database you are searching allows for it, search strategies such as Boolean searching, truncation and proximity operators, and other limiters can allow for numerous options to target the search.  Always make sure that you base subsequent searches on your initial results.  You can refine your search accordingly based on Boolean logic, or the addition or subtraction of search terms.

As technological advances are made, new opportunities to search across databases have arisen in recent years.  It will be interesting to see what new forms online database search takes as the future unfolds.


Bopp, Richard E., and Linda C. Smith.  Reference and Information Services: An Introduction.  4th ed. Santa Barbara, California: Libraries Unlimited, 2011.

Cassell, Kay Ann, and Uma Hiremath.  Reference and Information Services in the 21st Century: An Introduction.  2nd ed. New York: Neal-Schuman, 2009.

Curtis, AnneMarie, and Daniel G. Dormer. “Why Federated Search?.” Knowledge Quest 33.3 (2005): 35-37. Library, Information Science & Technology Abstracts. Web. 27 Nov. 2012.

“EBSCOhost Online Research Database: Advanced Search Screen 2.0.”  EBSCO.  2012.  Web.  27 Nov. 2012.

Fagan, Jody Condit. “Federated Search Is Dead-And Good Riddance!.” Journal Of Web Librarianship 5.2 (2011): 77-79. Library, Information Science & Technology Abstracts. Web. 27 Nov. 2012.

Ford, Charlotte.  Crash Course in Reference.  Westport, Connecticut: Libraries Unlimited, 2008

Stern, David. “Harvesting: Power And Opportunities Beyond Federated Search.” Online (Weston, Conn.) 33.4 (2009): 35-37. Library Literature & Information Science Full Text (H.W. Wilson). Web. 27 Nov. 2012.


2 thoughts on “Online Database Search Fundamentals

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s